Merge remote-tracking branch 'upstream/master' into symlink-review

2024-11-25 00:02:25 +00:00 · 2024-01-22 12:20:00 -05:00 · 2024-01-22 12:20:00 -05:00 · 73e6fc7966
commit 73e6fc7966
parent 5e3799bb69 50ce3832dc
589 changed files with 13875 additions and 6376 deletions
--- a/.clang-format
+++ b/.clang-format
@ -0,0 +1,30 @@
+BasedOnStyle: LLVM
+IndentWidth: 4
+BreakBeforeBraces: Custom
+BraceWrapping:
+  AfterStruct: true
+  AfterClass: true
+  AfterFunction: true
+  AfterUnion: true
+  SplitEmptyRecord: false
+PointerAlignment: Middle
+FixNamespaceComments: false
+SortIncludes: Never
+#IndentPPDirectives: BeforeHash
+SpaceAfterCStyleCast: true
+SpaceAfterTemplateKeyword: false
+AccessModifierOffset: -4
+AlignAfterOpenBracket: AlwaysBreak
+AlignEscapedNewlines: DontAlign
+ColumnLimit: 120
+BreakStringLiterals: false
+BitFieldColonSpacing: None
+AllowShortFunctionsOnASingleLine: Empty
+AlwaysBreakTemplateDeclarations: Yes
+BinPackParameters: false
+BreakConstructorInitializers: BeforeComma
+EmptyLineAfterAccessModifier: Leave # change to always/never later?
+EmptyLineBeforeAccessModifier: Leave
+#PackConstructorInitializers: BinPack
+BreakBeforeBinaryOperators: NonAssignment
+AlwaysBreakBeforeMultilineStrings: true
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@ -10,9 +10,8 @@
 # This file
 .github/CODEOWNERS @edolstra

-# Public documentation
-/doc @fricklerhandwerk
-*.md @fricklerhandwerk
+# Documentation of built-in functions
+src/libexpr/primops.cc @roberth

 # Libstore layer
 /src/libstore @thufschmitt
--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@ -10,6 +10,8 @@

 <!-- Large change: Provide instructions to reviewers how to read the diff. -->

-# Priorities
+# Priorities and Process

 Add :+1: to [pull requests you find important](https://github.com/NixOS/nix/pulls?q=is%3Aopen+sort%3Areactions-%2B1-desc).
+
+The Nix maintainer team uses a [GitHub project board](https://github.com/orgs/NixOS/projects/19) to [schedule and track reviews](https://github.com/NixOS/nix/tree/master/maintainers#project-board-protocol). 
--- a/.github/labeler.yml
+++ b/.github/labeler.yml
@ -1,23 +1,30 @@
 "documentation":
-  - doc/manual/*
-  - src/nix/**/*.md
+  - changed-files:
+    - any-glob-to-any-file: "doc/manual/*"
+    - any-glob-to-any-file: "src/nix/**/*.md"

 "store":
-  - src/libstore/store-api.*
-  - src/libstore/*-store.*
+  - changed-files:
+    - any-glob-to-any-file: "src/libstore/store-api.*"
+    - any-glob-to-any-file: "src/libstore/*-store.*"

 "fetching":
-  - src/libfetchers/**/*
+  - changed-files:
+    - any-glob-to-any-file: "src/libfetchers/**/*"

 "repl":
-  - src/libcmd/repl.*
-  - src/nix/repl.*
+  - changed-files:
+    - any-glob-to-any-file: "src/libcmd/repl.*"
+    - any-glob-to-any-file: "src/nix/repl.*"

 "new-cli":
-  - src/nix/**/*
+  - changed-files:
+    - any-glob-to-any-file: "src/nix/**/*"

 "with-tests":
+  - changed-files:
    # Unit tests
-  - src/*/tests/**/*
+    - any-glob-to-any-file: "src/*/tests/**/*"
    # Functional and integration tests
-  - tests/functional/**/*
+    - any-glob-to-any-file: "tests/functional/**/*"
+    
--- a/.github/workflows/backport.yml
+++ b/.github/workflows/backport.yml
@ -21,7 +21,7 @@ jobs:
          fetch-depth: 0
      - name: Create backport PRs
        # should be kept in sync with `version`
-        uses: zeebe-io/backport-action@v2.1.1
+        uses: zeebe-io/backport-action@v2.3.0
        with:
          # Config README: https://github.com/zeebe-io/backport-action#backport-action
          github_token: ${{ secrets.GITHUB_TOKEN }}
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@ -20,12 +20,12 @@ jobs:
    - uses: actions/checkout@v4
      with:
        fetch-depth: 0
-    - uses: cachix/install-nix-action@v23
+    - uses: cachix/install-nix-action@v25
      with:
        # The sandbox would otherwise be disabled by default on Darwin
        extra_nix_config: "sandbox = true"
    - run: echo CACHIX_NAME="$(echo $GITHUB_REPOSITORY-install-tests | tr "[A-Z]/" "[a-z]-")" >> $GITHUB_ENV
-    - uses: cachix/cachix-action@v12
+    - uses: cachix/cachix-action@v14
      if: needs.check_secrets.outputs.cachix == 'true'
      with:
        name: '${{ env.CACHIX_NAME }}'
@ -62,10 +62,10 @@ jobs:
      with:
        fetch-depth: 0
    - run: echo CACHIX_NAME="$(echo $GITHUB_REPOSITORY-install-tests | tr "[A-Z]/" "[a-z]-")" >> $GITHUB_ENV
-    - uses: cachix/install-nix-action@v23
+    - uses: cachix/install-nix-action@v25
      with:
        install_url: https://releases.nixos.org/nix/nix-2.13.3/install
-    - uses: cachix/cachix-action@v12
+    - uses: cachix/cachix-action@v14
      with:
        name: '${{ env.CACHIX_NAME }}'
        signingKey: '${{ secrets.CACHIX_SIGNING_KEY }}'
@ -84,7 +84,7 @@ jobs:
    steps:
    - uses: actions/checkout@v4
    - run: echo CACHIX_NAME="$(echo $GITHUB_REPOSITORY-install-tests | tr "[A-Z]/" "[a-z]-")" >> $GITHUB_ENV
-    - uses: cachix/install-nix-action@v23
+    - uses: cachix/install-nix-action@v25
      with:
        install_url: '${{needs.installer.outputs.installerURL}}'
        install_options: "--tarball-url-prefix https://${{ env.CACHIX_NAME }}.cachix.org/serve"
@ -114,12 +114,12 @@ jobs:
    - uses: actions/checkout@v4
      with:
        fetch-depth: 0
-    - uses: cachix/install-nix-action@v23
+    - uses: cachix/install-nix-action@v25
      with:
        install_url: https://releases.nixos.org/nix/nix-2.13.3/install
    - run: echo CACHIX_NAME="$(echo $GITHUB_REPOSITORY-install-tests | tr "[A-Z]/" "[a-z]-")" >> $GITHUB_ENV
    - run: echo NIX_VERSION="$(nix --experimental-features 'nix-command flakes' eval .\#default.version | tr -d \")" >> $GITHUB_ENV
-    - uses: cachix/cachix-action@v12
+    - uses: cachix/cachix-action@v14
      if: needs.check_secrets.outputs.cachix == 'true'
      with:
        name: '${{ env.CACHIX_NAME }}'
--- a/.github/workflows/labels.yml
+++ b/.github/workflows/labels.yml
@ -18,7 +18,7 @@ jobs:
    runs-on: ubuntu-latest
    if: github.repository_owner == 'NixOS'
    steps:
-    - uses: actions/labeler@v4
+    - uses: actions/labeler@v5
      with:
        repo-token: ${{ secrets.GITHUB_TOKEN }}
        sync-labels: false
--- a/.gitignore
+++ b/.gitignore
@ -21,12 +21,16 @@ perl/Makefile.config
 /doc/manual/language.json
 /doc/manual/xp-features.json
 /doc/manual/src/SUMMARY.md
+/doc/manual/src/SUMMARY-rl-next.md
+/doc/manual/src/store/types/*
+!/doc/manual/src/store/types/index.md.in
 /doc/manual/src/command-ref/new-cli
 /doc/manual/src/command-ref/conf-file.md
 /doc/manual/src/command-ref/experimental-features-shortlist.md
 /doc/manual/src/contributing/experimental-feature-descriptions.md
 /doc/manual/src/language/builtins.md
 /doc/manual/src/language/builtin-constants.md
+/doc/manual/src/release-notes/rl-next.md

 # /scripts/
 /scripts/nix-profile.sh
@ -41,21 +45,21 @@ perl/Makefile.config
 /src/libexpr/parser-tab.hh
 /src/libexpr/parser-tab.output
 /src/libexpr/nix.tbl
-/src/libexpr/tests/libnixexpr-tests
+/tests/unit/libexpr/libnixexpr-tests

 # /src/libfetchers
-/src/libfetchers/tests/libnixfetchers-tests
+/tests/unit/libfetchers/libnixfetchers-tests

 # /src/libstore/
 *.gen.*
-/src/libstore/tests/libnixstore-tests
+/tests/unit/libstore/libnixstore-tests

 # /src/libutil/
-/src/libutil/tests/libnixutil-tests
+/tests/unit/libutil/libnixutil-tests

 /src/nix/nix

-/src/nix/doc
+/src/nix/generated-doc

 # /src/nix-env/
 /src/nix-env/nix-env
@ -140,6 +144,7 @@ compile_commands.json
 nix-rust/target

 result
+result-*

 # IDE
 .vscode/
@ -147,3 +152,6 @@ result

 # clangd and possibly more
 .cache/
+
+# Mac OS
+.DS_Store
--- a/.version
+++ b/.version
@ -1 +1 @@
-2.19.0
+2.20.0
--- a/94
+++ b/94
@ -1,5 +1,11 @@
-include Makefile.config
-clean-files += Makefile.config
+# External build directory support
+
+include mk/build-dir.mk
+
+-include $(buildprefix)Makefile.config
+clean-files += $(buildprefix)Makefile.config
+
+# List makefiles

 ifeq ($(ENABLE_BUILD), yes)
 makefiles = \
@ -19,32 +25,31 @@ makefiles = \
  misc/zsh/local.mk \
  misc/systemd/local.mk \
  misc/launchd/local.mk \
-  misc/upstart/local.mk \
-  doc/manual/local.mk \
-  doc/internal-api/local.mk
+  misc/upstart/local.mk
 endif

-ifeq ($(ENABLE_BUILD)_$(ENABLE_TESTS), yes_yes)
-UNIT_TEST_ENV = _NIX_TEST_UNIT_DATA=unit-test-data
+ifeq ($(ENABLE_UNIT_TESTS), yes)
 makefiles += \
-  src/libutil/tests/local.mk \
-  src/libstore/tests/local.mk \
-  src/libfetchers/tests/local.mk \
-  src/libexpr/tests/local.mk
+  tests/unit/libutil/local.mk \
+  tests/unit/libutil-support/local.mk \
+  tests/unit/libstore/local.mk \
+  tests/unit/libstore-support/local.mk \
+  tests/unit/libfetchers/local.mk \
+  tests/unit/libexpr/local.mk \
+  tests/unit/libexpr-support/local.mk
 endif

-ifeq ($(ENABLE_TESTS), yes)
+ifeq ($(ENABLE_FUNCTIONAL_TESTS), yes)
 makefiles += \
  tests/functional/local.mk \
  tests/functional/ca/local.mk \
  tests/functional/dyn-drv/local.mk \
  tests/functional/test-libstoreconsumer/local.mk \
  tests/functional/plugins/local.mk
-else
-makefiles += \
-  mk/disable-tests.mk
 endif

+# Miscellaneous global Flags
+
 OPTIMIZE = 1

 ifeq ($(OPTIMIZE), 1)
@ -54,6 +59,63 @@ else
  GLOBAL_CXXFLAGS += -O0 -U_FORTIFY_SOURCE
 endif

+include mk/platform.mk
+
+ifdef HOST_WINDOWS
+  # Windows DLLs are stricter about symbol visibility than Unix shared
+  # objects --- see https://gcc.gnu.org/wiki/Visibility for details.
+  # This is a temporary sledgehammer to export everything like on Unix,
+  # and not detail with this yet.
+  #
+  # TODO do not do this, and instead do fine-grained export annotations.
+  GLOBAL_LDFLAGS += -Wl,--export-all-symbols
+endif
+
+GLOBAL_CXXFLAGS += -g -Wall -include $(buildprefix)config.h -std=c++2a -I src
+
+# Include the main lib, causing rules to be defined
+
 include mk/lib.mk

-GLOBAL_CXXFLAGS += -g -Wall -include config.h -std=c++2a -I src
+# Fallback stub rules for better UX when things are disabled
+#
+# These must be defined after `mk/lib.mk`. Otherwise the first rule
+# incorrectly becomes the default target.
+
+ifneq ($(ENABLE_UNIT_TESTS), yes)
+.PHONY: check
+check:
+	@echo "Unit tests are disabled. Configure without '--disable-unit-tests', or avoid calling 'make check'."
+	@exit 1
+endif
+
+ifneq ($(ENABLE_FUNCTIONAL_TESTS), yes)
+.PHONY: installcheck
+installcheck:
+	@echo "Functional tests are disabled. Configure without '--disable-functional-tests', or avoid calling 'make installcheck'."
+	@exit 1
+endif
+
+# Documentation or else fallback stub rules.
+#
+# The documentation makefiles be included after `mk/lib.mk` so rules
+# refer to variables defined by `mk/lib.mk`. Rules are not "lazy" like
+# variables, unfortunately.
+
+ifeq ($(ENABLE_DOC_GEN), yes)
+$(eval $(call include-sub-makefile, doc/manual/local.mk))
+else
+.PHONY: manual-html manpages
+manual-html manpages:
+	@echo "Generated docs are disabled. Configure without '--disable-doc-gen', or avoid calling 'make manpages' and 'make manual-html'."
+	@exit 1
+endif
+
+ifeq ($(ENABLE_INTERNAL_API_DOCS), yes)
+$(eval $(call include-sub-makefile, doc/internal-api/local.mk))
+else
+.PHONY: internal-api-html
+internal-api-html:
+	@echo "Internal API docs are disabled. Configure with '--enable-internal-api-docs', or avoid calling 'make internal-api-html'."
+	@exit 1
+endif
--- a/Makefile.config.in
+++ b/Makefile.config.in
@ -8,21 +8,27 @@ CXX = @CXX@
 CXXFLAGS = @CXXFLAGS@
 CXXLTO = @CXXLTO@
 EDITLINE_LIBS = @EDITLINE_LIBS@
+ENABLE_BUILD = @ENABLE_BUILD@
+ENABLE_DOC_GEN = @ENABLE_DOC_GEN@
+ENABLE_FUNCTIONAL_TESTS = @ENABLE_FUNCTIONAL_TESTS@
+ENABLE_INTERNAL_API_DOCS = @ENABLE_INTERNAL_API_DOCS@
 ENABLE_S3 = @ENABLE_S3@
+ENABLE_UNIT_TESTS = @ENABLE_UNIT_TESTS@
 GTEST_LIBS = @GTEST_LIBS@
 HAVE_LIBCPUID = @HAVE_LIBCPUID@
 HAVE_SECCOMP = @HAVE_SECCOMP@
 HOST_OS = @host_os@
+INSTALL_UNIT_TESTS = @INSTALL_UNIT_TESTS@
 LDFLAGS = @LDFLAGS@
 LIBARCHIVE_LIBS = @LIBARCHIVE_LIBS@
 LIBBROTLI_LIBS = @LIBBROTLI_LIBS@
 LIBCURL_LIBS = @LIBCURL_LIBS@
+LIBGIT2_LIBS = @LIBGIT2_LIBS@
 LIBSECCOMP_LIBS = @LIBSECCOMP_LIBS@
 LOWDOWN_LIBS = @LOWDOWN_LIBS@
 OPENSSL_LIBS = @OPENSSL_LIBS@
 PACKAGE_NAME = @PACKAGE_NAME@
 PACKAGE_VERSION = @PACKAGE_VERSION@
-RAPIDCHECK_HEADERS = @RAPIDCHECK_HEADERS@
 SHELL = @bash@
 SODIUM_LIBS = @SODIUM_LIBS@
 SQLITE3_LIBS = @SQLITE3_LIBS@
@ -32,7 +38,6 @@ checkbindir = @checkbindir@
 checklibdir = @checklibdir@
 datadir = @datadir@
 datarootdir = @datarootdir@
-doc_generate = @doc_generate@
 docdir = @docdir@
 embedded_sandbox_shell = @embedded_sandbox_shell@
 exec_prefix = @exec_prefix@
@ -48,7 +53,3 @@ sandbox_shell = @sandbox_shell@
 storedir = @storedir@
 sysconfdir = @sysconfdir@
 system = @system@
-ENABLE_BUILD = @ENABLE_BUILD@
-ENABLE_TESTS = @ENABLE_TESTS@
-INSTALL_UNIT_TESTS = @INSTALL_UNIT_TESTS@
-internal_api_docs = @internal_api_docs@
--- a/configure.ac
+++ b/configure.ac
@ -122,7 +122,6 @@ AC_PATH_PROG(flex, flex, false)
 AC_PATH_PROG(bison, bison, false)
 AC_PATH_PROG(dot, dot)
 AC_PATH_PROG(lsof, lsof, lsof)
-NEED_PROG(jq, jq)


 AC_SUBST(coreutils, [$(dirname $(type -p cat))])
@ -133,6 +132,48 @@ AC_ARG_WITH(store-dir, AS_HELP_STRING([--with-store-dir=PATH],[path of the Nix s
 AC_SUBST(storedir)


+# Running the functional tests without building Nix is useful for testing
+# different pre-built versions of Nix against each other.
+AC_ARG_ENABLE(build, AS_HELP_STRING([--disable-build],[Do not build nix]),
+  ENABLE_BUILD=$enableval, ENABLE_BUILD=yes)
+AC_SUBST(ENABLE_BUILD)
+
+# Building without unit tests is useful for bootstrapping with a smaller footprint
+# or running the tests in a separate derivation. Otherwise, we do compile and
+# run them.
+
+AC_ARG_ENABLE(unit-tests, AS_HELP_STRING([--disable-unit-tests],[Do not build the tests]),
+  ENABLE_UNIT_TESTS=$enableval, ENABLE_UNIT_TESTS=$ENABLE_BUILD)
+AC_SUBST(ENABLE_UNIT_TESTS)
+
+AS_IF(
+  [test "$ENABLE_BUILD" == "no" && test "$ENABLE_UNIT_TESTS" == "yes"],
+  [AC_MSG_ERROR([Cannot enable unit tests when building overall is disabled. Please do not pass '--enable-unit-tests' or do not pass '--disable-build'.])])
+
+AC_ARG_ENABLE(functional-tests, AS_HELP_STRING([--disable-functional-tests],[Do not build the tests]),
+  ENABLE_FUNCTIONAL_TESTS=$enableval, ENABLE_FUNCTIONAL_TESTS=yes)
+AC_SUBST(ENABLE_FUNCTIONAL_TESTS)
+
+# documentation generation switch
+AC_ARG_ENABLE(doc-gen, AS_HELP_STRING([--disable-doc-gen],[disable documentation generation]),
+  ENABLE_DOC_GEN=$enableval, ENABLE_DOC_GEN=$ENABLE_BUILD)
+AC_SUBST(ENABLE_DOC_GEN)
+
+AS_IF(
+  [test "$ENABLE_BUILD" == "no" && test "$ENABLE_DOC_GEN" == "yes"],
+  [AC_MSG_ERROR([Cannot enable generated docs when building overall is disabled. Please do not pass '--enable-doc-gen' or do not pass '--disable-build'.])])
+
+# Building without API docs is the default as Nix' C++ interfaces are internal and unstable.
+AC_ARG_ENABLE(internal-api-docs, AS_HELP_STRING([--enable-internal-api-docs],[Build API docs for Nix's internal unstable C++ interfaces]),
+  ENABLE_INTERNAL_API_DOCS=$enableval, ENABLE_INTERNAL_API_DOCS=no)
+AC_SUBST(ENABLE_INTERNAL_API_DOCS)
+
+AS_IF(
+  [test "$ENABLE_FUNCTIONAL_TESTS" == "yes" || test "$ENABLE_DOC_GEN" == "yes"],
+  [NEED_PROG(jq, jq)])
+
+AS_IF([test "$ENABLE_BUILD" == "yes"],[
+
 # Look for boost, a required dependency.
 # Note that AX_BOOST_BASE only exports *CPP* BOOST_CPPFLAGS, no CXX flags,
 # and CPPFLAGS are not passed to the C++ compiler automatically.
@ -155,18 +196,6 @@ if test "x$GCC_ATOMIC_BUILTINS_NEED_LIBATOMIC" = xyes; then
    LDFLAGS="-latomic $LDFLAGS"
 fi

-# Running the functional tests without building Nix is useful for testing
-# different pre-built versions of Nix against each other.
-AC_ARG_ENABLE(build, AS_HELP_STRING([--disable-build],[Do not build nix]),
-  ENABLE_BUILD=$enableval, ENABLE_BUILD=yes)
-AC_SUBST(ENABLE_BUILD)
-# Building without tests is useful for bootstrapping with a smaller footprint
-# or running the tests in a separate derivation. Otherwise, we do compile and
-# run them.
-AC_ARG_ENABLE(tests, AS_HELP_STRING([--disable-tests],[Do not build the tests]),
-  ENABLE_TESTS=$enableval, ENABLE_TESTS=yes)
-AC_SUBST(ENABLE_TESTS)
-
 AC_ARG_ENABLE(install-unit-tests, AS_HELP_STRING([--enable-install-unit-tests],[Install the unit tests for running later (default no)]),
  INSTALL_UNIT_TESTS=$enableval, INSTALL_UNIT_TESTS=no)
 AC_SUBST(INSTALL_UNIT_TESTS)
@ -179,11 +208,6 @@ AC_ARG_WITH(check-lib-dir, AS_HELP_STRING([--with-check-lib-dir=PATH],[path to i
  checklibdir=$withval, checklibdir=$libdir)
 AC_SUBST(checklibdir)

-# Building without API docs is the default as Nix' C++ interfaces are internal and unstable.
-AC_ARG_ENABLE(internal_api_docs, AS_HELP_STRING([--enable-internal-api-docs],[Build API docs for Nix's internal unstable C++ interfaces]),
-  internal_api_docs=$enableval, internal_api_docs=no)
-AC_SUBST(internal_api_docs)
-
 # LTO is currently broken with clang for unknown reasons; ld segfaults in the llvm plugin
 AC_ARG_ENABLE(lto, AS_HELP_STRING([--enable-lto],[Enable LTO (only supported with GCC) [default=no]]),
  lto=$enableval, lto=no)
@ -227,17 +251,25 @@ PKG_CHECK_MODULES([SQLITE3], [sqlite3 >= 3.6.19], [CXXFLAGS="$SQLITE3_CFLAGS $CX
 # Look for libcurl, a required dependency.
 PKG_CHECK_MODULES([LIBCURL], [libcurl], [CXXFLAGS="$LIBCURL_CFLAGS $CXXFLAGS"])

-# Look for editline, a required dependency.
+# Look for editline or readline, a required dependency.
 # The the libeditline.pc file was added only in libeditline >= 1.15.2,
 # see https://github.com/troglobit/editline/commit/0a8f2ef4203c3a4a4726b9dd1336869cd0da8607,
-# but e.g. Ubuntu 16.04 has an older version, so we fall back to searching for
-# editline.h when the pkg-config approach fails.
-PKG_CHECK_MODULES([EDITLINE], [libeditline], [CXXFLAGS="$EDITLINE_CFLAGS $CXXFLAGS"], [
-  AC_CHECK_HEADERS([editline.h], [true],
-    [AC_MSG_ERROR([Nix requires libeditline; it was found neither via pkg-config nor its normal header.])])
-  AC_SEARCH_LIBS([readline read_history], [editline], [],
-    [AC_MSG_ERROR([Nix requires libeditline; it was not found via pkg-config, but via its header, but required functions do not work. Maybe it is too old? >= 1.14 is required.])])
-])
+# Older versions are no longer supported.
+AC_ARG_WITH(
+  [readline-flavor],
+  AS_HELP_STRING([--with-readline-flavor],[Which library to use for nice line editting with the Nix language REPL" [default=editline]]),
+  [readline_flavor=$withval],
+  [readline_flavor=editline])
+AS_CASE(["$readline_flavor"],
+  [editline], [
+    readline_flavor_pc=libeditline
+  ],
+  [readline], [
+    readline_flavor_pc=readline
+    AC_DEFINE([USE_READLINE], [1], [Use readline instead of editline])
+  ],
+  [AC_MSG_ERROR([bad value "$readline_flavor" for --with-readline-flavor, must be one of: editline, readline])])
+PKG_CHECK_MODULES([EDITLINE], [$readline_flavor_pc], [CXXFLAGS="$EDITLINE_CFLAGS $CXXFLAGS"])

 # Look for libsodium.
 PKG_CHECK_MODULES([SODIUM], [libsodium], [CXXFLAGS="$SODIUM_CFLAGS $CXXFLAGS"])
@ -282,6 +314,14 @@ case "$host_os" in
 esac
 AC_SUBST(HAVE_SECCOMP, [$have_seccomp])

+# Optional dependencies for better normalizing file system data
+AC_CHECK_HEADERS([sys/xattr.h])
+AS_IF([test "$ac_cv_header_sys_xattr_h" = "yes"],[
+  AC_CHECK_FUNCS([llistxattr lremovexattr])
+  AS_IF([test "$ac_cv_func_llistxattr" = "yes" && test "$ac_cv_func_lremovexattr" = "yes"],[
+    AC_DEFINE([HAVE_ACL_SUPPORT], [1], [Define if we can manipulate file system Access Control Lists])
+  ])
+])

 # Look for aws-cpp-sdk-s3.
 AC_LANG_PUSH(C++)
@ -308,47 +348,40 @@ if test "$gc" = yes; then
  AC_DEFINE(HAVE_BOEHMGC, 1, [Whether to use the Boehm garbage collector.])
 fi

-
-if test "$ENABLE_TESTS" = yes; then
+AS_IF([test "$ENABLE_UNIT_TESTS" == "yes"],[

 # Look for gtest.
 PKG_CHECK_MODULES([GTEST], [gtest_main])

-
 # Look for rapidcheck.
-AC_ARG_VAR([RAPIDCHECK_HEADERS], [include path of gtest headers shipped by RAPIDCHECK])
-# No pkg-config yet, https://github.com/emil-e/rapidcheck/issues/302
-AC_LANG_PUSH(C++)
-AC_SUBST(RAPIDCHECK_HEADERS)
-[CXXFLAGS="-I $RAPIDCHECK_HEADERS $CXXFLAGS"]
-[LIBS="-lrapidcheck -lgtest $LIBS"]
-AC_CHECK_HEADERS([rapidcheck/gtest.h], [], [], [#include <gtest/gtest.h>])
-dnl AC_CHECK_LIB doesn't work for C++ libs with mangled symbols
-AC_LINK_IFELSE([
-    AC_LANG_PROGRAM([[
-      #include <gtest/gtest.h>
-      #include <rapidcheck/gtest.h>
-    ]], [[
-      return RUN_ALL_TESTS();
-    ]])
-  ],
-  [],
-  [AC_MSG_ERROR([librapidcheck is not found.])])
-AC_LANG_POP(C++)
+PKG_CHECK_MODULES([RAPIDCHECK], [rapidcheck rapidcheck_gtest])

-fi
+])

 # Look for nlohmann/json.
 PKG_CHECK_MODULES([NLOHMANN_JSON], [nlohmann_json >= 3.9])


-# documentation generation switch
-AC_ARG_ENABLE(doc-gen, AS_HELP_STRING([--disable-doc-gen],[disable documentation generation]),
-  doc_generate=$enableval, doc_generate=yes)
-AC_SUBST(doc_generate)
-
 # Look for lowdown library.
-PKG_CHECK_MODULES([LOWDOWN], [lowdown >= 0.9.0], [CXXFLAGS="$LOWDOWN_CFLAGS $CXXFLAGS"])
+AC_ARG_ENABLE([markdown], AS_HELP_STRING([--enable-markdown], [Enable Markdown rendering in the Nix binary (requires lowdown) [default=auto]]),
+  enable_markdown=$enableval, enable_markdown=auto)
+AS_CASE(["$enable_markdown"],
+  [yes | auto], [
+    PKG_CHECK_MODULES([LOWDOWN], [lowdown >= 0.9.0], [
+      CXXFLAGS="$LOWDOWN_CFLAGS $CXXFLAGS"
+      have_lowdown=1
+      AC_DEFINE(HAVE_LOWDOWN, 1, [Whether lowdown is available and should be used for Markdown rendering.])
+    ], [
+      AS_IF([test "x$enable_markdown" == "xyes"], [AC_MSG_ERROR([--enable-markdown was specified, but lowdown was not found.])])
+    ])
+  ],
+  [no], [have_lowdown=],
+  [AC_MSG_ERROR([bad value "$enable_markdown" for --enable-markdown, must be one of: yes, no, auto])])
+
+
+# Look for libgit2.
+PKG_CHECK_MODULES([LIBGIT2], [libgit2])
+

 # Setuid installations.
 AC_CHECK_FUNCS([setresuid setreuid lchown])
@ -380,6 +413,8 @@ if test "$embedded_sandbox_shell" = yes; then
  AC_DEFINE(HAVE_EMBEDDED_SANDBOX_SHELL, 1, [Include the sandbox shell in the Nix binary.])
 fi

+])
+

 # Expand all variables in config.status.
 test "$prefix" = NONE && prefix=$ac_default_prefix
--- a/dep-patches/boehmgc-coroutine-sp-fallback.diff
+++ b/dep-patches/boehmgc-coroutine-sp-fallback.diff
--- a/dep-patches/boehmgc-traceable_allocator-public.diff
+++ b/dep-patches/boehmgc-traceable_allocator-public.diff
@ -0,0 +1,12 @@
+diff --git a/include/gc_allocator.h b/include/gc_allocator.h
+index 597c7f13..587286be 100644
+--- a/include/gc_allocator.h
+++ b/include/gc_allocator.h
+@@ -312,6 +312,7 @@ public:
+ 
+ template<>
+ class traceable_allocator<void> {
+public:
+   typedef size_t      size_type;
+   typedef ptrdiff_t   difference_type;
+   typedef void*       pointer;
--- a/doc/internal-api/doxygen.cfg.in
+++ b/doc/internal-api/doxygen.cfg.in
@ -39,17 +39,21 @@ INPUT                  = \
  src/libcmd \
  src/libexpr \
  src/libexpr/flake \
-  src/libexpr/tests \
-  src/libexpr/tests/value \
+  tests/unit/libexpr \
+  tests/unit/libexpr/value \
+  tests/unit/libexpr/test \
+  tests/unit/libexpr/test/value \
  src/libexpr/value \
  src/libfetchers \
  src/libmain \
  src/libstore \
  src/libstore/build \
  src/libstore/builtins \
-  src/libstore/tests \
+  tests/unit/libstore \
+  tests/unit/libstore/test \
  src/libutil \
-  src/libutil/tests \
+  tests/unit/libutil \
+  tests/unit/libutil/test \
  src/nix \
  src/nix-env \
  src/nix-store
@ -77,7 +81,7 @@ EXPAND_ONLY_PREDEF     = YES
 # RECURSIVE has no effect here.
 # This tag requires that the tag SEARCH_INCLUDES is set to YES.

-INCLUDE_PATH           = @RAPIDCHECK_HEADERS@
+INCLUDE_PATH           =

 # If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then this
 # tag can be used to specify a list of macro names that should be expanded. The
--- a/doc/internal-api/local.mk
+++ b/doc/internal-api/local.mk
@ -1,19 +1,7 @@
-.PHONY: internal-api-html
-
-ifeq ($(internal_api_docs), yes)
-
 $(docdir)/internal-api/html/index.html $(docdir)/internal-api/latex: $(d)/doxygen.cfg
 	mkdir -p $(docdir)/internal-api
 	{ cat $< ; echo "OUTPUT_DIRECTORY=$(docdir)/internal-api" ; } | doxygen -

 # Generate the HTML API docs for Nix's unstable internal interfaces.
+.PHONY: internal-api-html
 internal-api-html: $(docdir)/internal-api/html/index.html
-
-else
-
-# Make a nicer error message
-internal-api-html:
-	@echo "Internal API docs are disabled. Configure with '--enable-internal-api-docs', or avoid calling 'make internal-api-html'."
-	@exit 1
-
-endif
--- a/doc/manual/_redirects
+++ b/doc/manual/_redirects
@ -0,0 +1,40 @@
+# redirect rules for paths (server-side) to prevent link rot.
+# see ./redirects.js for redirects based on URL fragments (client-side)
+#
+# concrete user story this supports:
+# - user finds URL to the manual for Nix x.y
+# - Nix x.z (z > y) is the most recent release
+# - updating the version in the URL will show the right thing
+#
+# format documentation:
+# - https://docs.netlify.com/routing/redirects/#syntax-for-the-redirects-file
+# - https://docs.netlify.com/routing/redirects/redirect-options/
+#
+# conventions:
+# - always force (<CODE>!) since this allows re-using file names
+# - group related paths to ease readability
+# - keep in alphabetical/wildcards-last order, which will reduce version control conflicts
+# - redirects that should have been there but are missing can be inserted where they belong
+
+/advanced-topics/advanced-topics /advanced-topics 301!
+
+/command-ref/command-ref /command-ref 301!
+
+/contributing/contributing /contributing 301!
+
+/expressions/expression-language /language/ 301!
+/expressions/language-constructs /language/constructs 301!
+/expressions/language-operators /language/operators 301!
+/expressions/language-values /language/values 301!
+/expressions/* /language/:splat 301!
+
+/installation/installation /installation 301!
+
+/package-management/basic-package-mgmt /command-ref/nix-env 301!
+/package-management/channels /command-ref/nix-channel 301!
+/package-management/package-management /package-management 301!
+/package-management/s3-substituter /store/types/s3-binary-cache-store 301!
+
+/protocols/protocols /protocols 301!
+
+/release-notes/release-notes /release-notes 301!
--- a/doc/manual/generate-builtin-constants.nix
+++ b/doc/manual/generate-builtin-constants.nix
@ -1,6 +1,6 @@
 let
  inherit (builtins) concatStringsSep attrValues mapAttrs;
-  inherit (import ./utils.nix) optionalString squash;
+  inherit (import <nix/utils.nix>) optionalString squash;
 in

 builtinsInfo:
--- a/doc/manual/generate-builtins.nix
+++ b/doc/manual/generate-builtins.nix
@ -1,6 +1,6 @@
 let
  inherit (builtins) concatStringsSep attrValues mapAttrs;
-  inherit (import ./utils.nix) optionalString squash;
+  inherit (import <nix/utils.nix>) optionalString squash;
 in

 builtinsInfo:
@ -8,7 +8,15 @@ let
  showBuiltin = name: { doc, args, arity, experimental-feature }:
    let
      experimentalNotice = optionalString (experimental-feature != null) ''
-        This function is only available if the [${experimental-feature}](@docroot@/contributing/experimental-features.md#xp-feature-${experimental-feature}) experimental feature is enabled.
+        > **Note**
+        >
+        > This function is only available if the [`${experimental-feature}` experimental feature](@docroot@/contributing/experimental-features.md#xp-feature-${experimental-feature}) is enabled.
+        >
+        > For example, include the following in [`nix.conf`](@docroot@/command-ref/conf-file.md):
+        >
+        > ```
+        > extra-experimental-features = ${experimental-feature}
+        > ```
      '';
    in
    squash ''
@ -17,10 +25,9 @@ let
      </dt>
      <dd>

-      ${doc}
-
      ${experimentalNotice}

+      ${doc}
      </dd>
    '';
  listArgs = args: concatStringsSep " " (map (s: "<var>${s}</var>") args);
--- a/doc/manual/generate-manpage.nix
+++ b/doc/manual/generate-manpage.nix
@ -1,9 +1,29 @@
 let
  inherit (builtins)
-    attrNames attrValues fromJSON listToAttrs mapAttrs groupBy
-    concatStringsSep concatMap length lessThan replaceStrings sort;
-  inherit (import <nix/utils.nix>) attrsToList concatStrings optionalString filterAttrs trim squash unique;
-  showStoreDocs = import ./generate-store-info.nix;
+    attrNames
+    attrValues
+    concatMap
+    concatStringsSep
+    fromJSON
+    groupBy
+    length
+    lessThan
+    listToAttrs
+    mapAttrs
+    match
+    replaceStrings
+    sort
+    ;
+  inherit (import <nix/utils.nix>)
+    attrsToList
+    concatStrings
+    filterAttrs
+    optionalString
+    squash
+    trim
+    unique
+    ;
+  showStoreDocs = import <nix/generate-store-info.nix>;
 in

 inlineHTML: commandDump:
@ -31,7 +51,7 @@ let

        ${maybeSubcommands}

-        ${maybeStoreDocs}
+        ${maybeProse}

        ${maybeOptions}
      '';
@ -71,17 +91,48 @@ let
        * [`${command} ${name}`](./${appendName filename name}.md) - ${subcmd.description}
      '';

-      # FIXME: this is a hack.
-      # store parameters should not be part of command documentation to begin
-      # with, but instead be rendered on separate pages.
-      maybeStoreDocs = optionalString (details ? doc)
-        (replaceStrings [ "@stores@" ] [ (showStoreDocs inlineHTML commandInfo.stores) ] details.doc);
+      maybeProse =
+        # FIXME: this is a horrible hack to keep `nix help-stores` working.
+        # the correct answer to this is to remove that command and replace it
+        # by statically generated manpages or the output of something like `nix
+        # store info <store type>`.
+        let
+          help-stores = ''
+            ${index}

-      maybeOptions = let
+            ${allStores}
+          '';
+          index = replaceStrings
+            [ "@store-types@" "./local-store.md" "./local-daemon-store.md" ]
+            [ storesOverview "#local-store" "#local-daemon-store" ]
+            details.doc;
+          storesOverview =
+            let
+              showEntry = store:
+                "- [${store.name}](#${store.slug})";
+            in
+            concatStringsSep "\n" (map showEntry storesList) + "\n";
+          allStores = concatStringsSep "\n" (attrValues storePages);
+          storePages = listToAttrs
+            (map (s: { name = s.filename; value = s.page; }) storesList);
+          storesList = showStoreDocs {
+            storeInfo = commandInfo.stores;
+            inherit inlineHTML;
+          };
+        in
+        optionalString (details ? doc) (
+          if match "@store-types@" details.doc != [ ]
+          then help-stores
+          else details.doc
+        );
+
+      maybeOptions =
+        let
          allVisibleOptions = filterAttrs
            (_: o: ! o.hiddenCategory)
            (details.flags // toplevel.flags);
-      in optionalString (allVisibleOptions != {}) ''
+        in
+        optionalString (allVisibleOptions != { }) ''
          # Options

          ${showOptions inlineHTML allVisibleOptions}
--- a/doc/manual/generate-settings.nix
+++ b/doc/manual/generate-settings.nix
@ -1,6 +1,6 @@
 let
  inherit (builtins) attrValues concatStringsSep isAttrs isBool mapAttrs;
-  inherit (import ./utils.nix) concatStrings indent optionalString squash;
+  inherit (import <nix/utils.nix>) concatStrings indent optionalString squash;
 in

 # `inlineHTML` is a hack to accommodate inconsistent output from `lowdown`
@ -20,10 +20,10 @@ let
        else "`${setting}`";
      # separate body to cleanly handle indentation
      body = ''
-          ${description}
-
          ${experimentalFeatureNote}

+          ${description}
+
          **Default:** ${showDefault documentDefault defaultValue}

          ${showAliases aliases}
@ -31,18 +31,19 @@ let

      experimentalFeatureNote = optionalString (experimentalFeature != null) ''
          > **Warning**
+          >
          > This setting is part of an
          > [experimental feature](@docroot@/contributing/experimental-features.md).
-
-          To change this setting, you need to make sure the corresponding experimental feature,
-          [`${experimentalFeature}`](@docroot@/contributing/experimental-features.md#xp-feature-${experimentalFeature}),
-          is enabled.
-          For example, include the following in [`nix.conf`](#):
-
-          ```
-          extra-experimental-features = ${experimentalFeature}
-          ${setting} = ...
-          ```
+          >
+          > To change this setting, make sure the
+          > [`${experimentalFeature}` experimental feature](@docroot@/contributing/experimental-features.md#xp-feature-${experimentalFeature})
+          > is enabled.
+          > For example, include the following in [`nix.conf`](@docroot@/command-ref/conf-file.md):
+          >
+          > ```
+          > extra-experimental-features = ${experimentalFeature}
+          > ${setting} = ...
+          > ```
        '';

      showDefault = documentDefault: defaultValue:
--- a/doc/manual/generate-store-info.nix
+++ b/doc/manual/generate-store-info.nix
@ -1,45 +1,57 @@
 let
-  inherit (builtins) attrValues mapAttrs;
-  inherit (import ./utils.nix) concatStrings optionalString;
-  showSettings = import ./generate-settings.nix;
+  inherit (builtins) attrNames listToAttrs concatStringsSep readFile replaceStrings;
+  inherit (import <nix/utils.nix>) optionalString filterAttrs trim squash toLower unique indent;
+  showSettings = import <nix/generate-settings.nix>;
 in

-inlineHTML: storesInfo:
+{
+  # data structure describing all stores and their parameters
+  storeInfo,
+  # whether to add inline HTML tags
+  # `lowdown` does not eat those for one of the output modes
+  inlineHTML,
+}:

 let

-  showStore = name: { settings, doc, experimentalFeature }:
+  showStore = { name, slug }: { settings, doc, experimentalFeature }:
    let
-
-    result = ''
-      ## ${name}
-
-      ${doc}
+      result = squash ''
+        # ${name}

        ${experimentalFeatureNote}

-      ### Settings
+        ${doc}
+
+        ## Settings

        ${showSettings { prefix = "store-${slug}"; inherit inlineHTML; } settings}
      '';

-      # markdown doesn't like spaces in URLs
-      slug = builtins.replaceStrings [ " " ] [ "-" ] name;
-
      experimentalFeatureNote = optionalString (experimentalFeature != null) ''
        > **Warning**
+        >
        > This store is part of an
        > [experimental feature](@docroot@/contributing/experimental-features.md).
-
-      To use this store, you need to make sure the corresponding experimental feature,
-      [`${experimentalFeature}`](@docroot@/contributing/experimental-features.md#xp-feature-${experimentalFeature}),
-      is enabled.
-      For example, include the following in [`nix.conf`](#):
-
-      ```
-      extra-experimental-features = ${experimentalFeature}
-      ```
+        >
+        > To use this store, make sure the
+        > [`${experimentalFeature}` experimental feature](@docroot@/contributing/experimental-features.md#xp-feature-${experimentalFeature})
+        > is enabled.
+        > For example, include the following in [`nix.conf`](@docroot@/command-ref/conf-file.md):
+        >
+        > ```
+        > extra-experimental-features = ${experimentalFeature}
+        > ```
      '';
    in result;

-in concatStrings (attrValues (mapAttrs showStore storesInfo))
+  storesList = map
+    (name: rec {
+      inherit name;
+      slug = replaceStrings [ " " ] [ "-" ] (toLower name);
+      filename = "${slug}.md";
+      page = showStore { inherit name slug; } storeInfo.${name};
+    })
+    (attrNames storeInfo);
+
+in storesList
--- a/doc/manual/generate-store-types.nix
+++ b/doc/manual/generate-store-types.nix
@ -0,0 +1,39 @@
+let
+  inherit (builtins) attrNames listToAttrs concatStringsSep readFile replaceStrings;
+  showSettings = import <nix/generate-settings.nix>;
+  showStoreDocs = import <nix/generate-store-info.nix>;
+in
+
+storeInfo:
+
+let
+  storesList = showStoreDocs {
+    inherit storeInfo;
+    inlineHTML = true;
+  };
+
+  index =
+    let
+      showEntry = store:
+        "- [${store.name}](./${store.filename})";
+    in
+    concatStringsSep "\n" (map showEntry storesList);
+
+  "index.md" = replaceStrings
+    [ "@store-types@" ] [ index ]
+    (readFile ./src/store/types/index.md.in);
+
+  tableOfContents =
+    let
+      showEntry = store:
+        "    - [${store.name}](store/types/${store.filename})";
+    in
+    concatStringsSep "\n" (map showEntry storesList) + "\n";
+
+  "SUMMARY.md" = tableOfContents;
+
+  storePages = listToAttrs
+    (map (s: { name = s.filename; value = s.page; }) storesList);
+
+in
+storePages // { inherit "index.md" "SUMMARY.md"; }
--- a/doc/manual/generate-xp-features-shortlist.nix
+++ b/doc/manual/generate-xp-features-shortlist.nix
@ -1,5 +1,5 @@
 with builtins;
-with import ./utils.nix;
+with import <nix/utils.nix>;

 let
  showExperimentalFeature = name: doc:
--- a/doc/manual/generate-xp-features.nix
+++ b/doc/manual/generate-xp-features.nix
@ -1,5 +1,5 @@
 with builtins;
-with import ./utils.nix;
+with import <nix/utils.nix>;

 let
  showExperimentalFeature = name: doc:
@ -8,4 +8,6 @@ let

      ${doc}
    '';
-in xps: (concatStringsSep "\n" (attrValues (mapAttrs showExperimentalFeature xps)))
+in
+
+xps: (concatStringsSep "\n" (attrValues (mapAttrs showExperimentalFeature xps)))
--- a/doc/manual/local.mk
+++ b/doc/manual/local.mk
@ -1,4 +1,7 @@
-ifeq ($(doc_generate),yes)
+# The version of Nix used to generate the doc. Can also be
+# `$(nix_INSTALL_PATH)` or just `nix` (to grap ambient from the `PATH`),
+# if one prefers.
+doc_nix = $(nix_PATH)

 MANUAL_SRCS := \
 	$(call rwildcard, $(d)/src, *.md) \
@ -24,7 +27,7 @@ man-pages += $(foreach subcommand, \
 clean-files += $(d)/*.1 $(d)/*.5 $(d)/*.8

 # Provide a dummy environment for nix, so that it will not access files outside the macOS sandbox.
-# Set cores to 0 because otherwise nix show-config resolves the cores based on the current machine
+# Set cores to 0 because otherwise `nix config show` resolves the cores based on the current machine
 dummy-env = env -i \
 	HOME=/dummy \
 	NIX_CONF_DIR=/dummy \
@ -32,7 +35,7 @@ dummy-env = env -i \
 	NIX_STATE_DIR=/dummy \
 	NIX_CONFIG='cores = 0'

-nix-eval = $(dummy-env) $(bindir)/nix eval --experimental-features nix-command -I nix=doc/manual --store dummy:// --impure --raw
+nix-eval = $(dummy-env) $(doc_nix) eval --experimental-features nix-command -I nix=doc/manual --store dummy:// --impure --raw

 # re-implement mdBook's include directive to make it usable for terminal output and for proper @docroot@ substitution
 define process-includes
@ -92,64 +95,91 @@ $(d)/nix-profiles.5: $(d)/src/command-ref/files/profiles.md
 	$(trace-gen) lowdown -sT man --nroff-nolinks -M section=5 $^.tmp -o $@
 	@rm $^.tmp

-$(d)/src/SUMMARY.md: $(d)/src/SUMMARY.md.in $(d)/src/command-ref/new-cli $(d)/src/contributing/experimental-feature-descriptions.md
+$(d)/src/SUMMARY.md: $(d)/src/SUMMARY.md.in $(d)/src/SUMMARY-rl-next.md $(d)/src/store/types $(d)/src/command-ref/new-cli $(d)/src/contributing/experimental-feature-descriptions.md
 	@cp $< $@
 	@$(call process-includes,$@,$@)

-$(d)/src/command-ref/new-cli: $(d)/nix.json $(d)/utils.nix $(d)/generate-manpage.nix $(d)/generate-settings.nix $(d)/generate-store-info.nix $(bindir)/nix
+$(d)/src/store/types: $(d)/nix.json $(d)/utils.nix $(d)/generate-store-info.nix  $(d)/generate-store-types.nix $(d)/src/store/types/index.md.in $(doc_nix)
+	@# FIXME: build out of tree!
+	@rm -rf $@.tmp
+	$(trace-gen) $(nix-eval) --write-to $@.tmp --expr 'import doc/manual/generate-store-types.nix (builtins.fromJSON (builtins.readFile $<)).stores'
+	@# do not destroy existing contents
+	@mv $@.tmp/* $@/
+
+$(d)/src/command-ref/new-cli: $(d)/nix.json $(d)/utils.nix $(d)/generate-manpage.nix $(d)/generate-settings.nix $(d)/generate-store-info.nix $(doc_nix)
 	@rm -rf $@ $@.tmp
 	$(trace-gen) $(nix-eval) --write-to $@.tmp --expr 'import doc/manual/generate-manpage.nix true (builtins.readFile $<)'
 	@mv $@.tmp $@

-$(d)/src/command-ref/conf-file.md: $(d)/conf-file.json $(d)/utils.nix $(d)/generate-settings.nix $(d)/src/command-ref/conf-file-prefix.md $(d)/src/command-ref/experimental-features-shortlist.md $(bindir)/nix
+$(d)/src/command-ref/conf-file.md: $(d)/conf-file.json $(d)/utils.nix $(d)/generate-settings.nix $(d)/src/command-ref/conf-file-prefix.md $(d)/src/command-ref/experimental-features-shortlist.md $(doc_nix)
 	@cat doc/manual/src/command-ref/conf-file-prefix.md > $@.tmp
 	$(trace-gen) $(nix-eval) --expr 'import doc/manual/generate-settings.nix { prefix = "conf"; } (builtins.fromJSON (builtins.readFile $<))' >> $@.tmp;
 	@mv $@.tmp $@

-$(d)/nix.json: $(bindir)/nix
-	$(trace-gen) $(dummy-env) $(bindir)/nix __dump-cli > $@.tmp
+$(d)/nix.json: $(doc_nix)
+	$(trace-gen) $(dummy-env) $(doc_nix) __dump-cli > $@.tmp
 	@mv $@.tmp $@

-$(d)/conf-file.json: $(bindir)/nix
-	$(trace-gen) $(dummy-env) $(bindir)/nix show-config --json --experimental-features nix-command > $@.tmp
+$(d)/conf-file.json: $(doc_nix)
+	$(trace-gen) $(dummy-env) $(doc_nix) config show --json --experimental-features nix-command > $@.tmp
 	@mv $@.tmp $@

-$(d)/src/contributing/experimental-feature-descriptions.md: $(d)/xp-features.json $(d)/utils.nix $(d)/generate-xp-features.nix $(bindir)/nix
+$(d)/src/contributing/experimental-feature-descriptions.md: $(d)/xp-features.json $(d)/utils.nix $(d)/generate-xp-features.nix $(doc_nix)
 	@rm -rf $@ $@.tmp
 	$(trace-gen) $(nix-eval) --write-to $@.tmp --expr 'import doc/manual/generate-xp-features.nix (builtins.fromJSON (builtins.readFile $<))'
 	@mv $@.tmp $@

-$(d)/src/command-ref/experimental-features-shortlist.md: $(d)/xp-features.json $(d)/utils.nix $(d)/generate-xp-features-shortlist.nix $(bindir)/nix
+$(d)/src/command-ref/experimental-features-shortlist.md: $(d)/xp-features.json $(d)/utils.nix $(d)/generate-xp-features-shortlist.nix $(doc_nix)
 	@rm -rf $@ $@.tmp
 	$(trace-gen) $(nix-eval) --write-to $@.tmp --expr 'import doc/manual/generate-xp-features-shortlist.nix (builtins.fromJSON (builtins.readFile $<))'
 	@mv $@.tmp $@

-$(d)/xp-features.json: $(bindir)/nix
-	$(trace-gen) $(dummy-env) $(bindir)/nix __dump-xp-features > $@.tmp
+$(d)/xp-features.json: $(doc_nix)
+	$(trace-gen) $(dummy-env) $(doc_nix) __dump-xp-features > $@.tmp
 	@mv $@.tmp $@

-$(d)/src/language/builtins.md: $(d)/language.json $(d)/generate-builtins.nix $(d)/src/language/builtins-prefix.md $(bindir)/nix
+$(d)/src/language/builtins.md: $(d)/language.json $(d)/generate-builtins.nix $(d)/src/language/builtins-prefix.md $(doc_nix)
 	@cat doc/manual/src/language/builtins-prefix.md > $@.tmp
 	$(trace-gen) $(nix-eval) --expr 'import doc/manual/generate-builtins.nix (builtins.fromJSON (builtins.readFile $<)).builtins' >> $@.tmp;
 	@cat doc/manual/src/language/builtins-suffix.md >> $@.tmp
 	@mv $@.tmp $@

-$(d)/src/language/builtin-constants.md: $(d)/language.json $(d)/generate-builtin-constants.nix $(d)/src/language/builtin-constants-prefix.md $(bindir)/nix
+$(d)/src/language/builtin-constants.md: $(d)/language.json $(d)/generate-builtin-constants.nix $(d)/src/language/builtin-constants-prefix.md $(doc_nix)
 	@cat doc/manual/src/language/builtin-constants-prefix.md > $@.tmp
 	$(trace-gen) $(nix-eval) --expr 'import doc/manual/generate-builtin-constants.nix (builtins.fromJSON (builtins.readFile $<)).constants' >> $@.tmp;
 	@cat doc/manual/src/language/builtin-constants-suffix.md >> $@.tmp
 	@mv $@.tmp $@

-$(d)/language.json: $(bindir)/nix
-	$(trace-gen) $(dummy-env) $(bindir)/nix __dump-language > $@.tmp
+$(d)/language.json: $(doc_nix)
+	$(trace-gen) $(dummy-env) $(doc_nix) __dump-language > $@.tmp
 	@mv $@.tmp $@

+# Generate "Upcoming release" notes (or clear it and remove from menu)
+$(d)/src/release-notes/rl-next.md: $(d)/rl-next $(d)/rl-next/*
+	@if type -p changelog-d > /dev/null; then \
+		echo "  GEN   " $@; \
+		changelog-d doc/manual/rl-next > $@; \
+	else \
+		echo "  NULL  " $@; \
+		true > $@; \
+	fi
+
+$(d)/src/SUMMARY-rl-next.md: $(d)/src/release-notes/rl-next.md
+	$(trace-gen) true
+	@if [ -s $< ]; then \
+		echo '  - [Upcoming release](release-notes/rl-next.md)' > $@; \
+	else \
+	  true > $@; \
+	fi
+
 # Generate the HTML manual.
 .PHONY: manual-html
 manual-html: $(docdir)/manual/index.html
 install: $(docdir)/manual/index.html

 # Generate 'nix' manpages.
+.PHONY: manpages
+manpages: $(mandir)/man1/nix3-manpages
 install: $(mandir)/man1/nix3-manpages
 man: doc/manual/generated/man1/nix3-manpages
 all: doc/manual/generated/man1/nix3-manpages
@ -177,7 +207,7 @@ doc/manual/generated/man1/nix3-manpages: $(d)/src/command-ref/new-cli
 # `@docroot@` is to be preserved for documenting the mechanism
 # FIXME: maybe contributing guides should live right next to the code
 # instead of in the manual
-$(docdir)/manual/index.html: $(MANUAL_SRCS) $(d)/book.toml $(d)/anchors.jq $(d)/custom.css $(d)/src/SUMMARY.md $(d)/src/command-ref/new-cli $(d)/src/contributing/experimental-feature-descriptions.md $(d)/src/command-ref/conf-file.md $(d)/src/language/builtins.md $(d)/src/language/builtin-constants.md
+$(docdir)/manual/index.html: $(MANUAL_SRCS) $(d)/book.toml $(d)/anchors.jq $(d)/custom.css $(d)/src/SUMMARY.md $(d)/src/store/types $(d)/src/command-ref/new-cli $(d)/src/contributing/experimental-feature-descriptions.md $(d)/src/command-ref/conf-file.md $(d)/src/language/builtins.md $(d)/src/language/builtin-constants.md $(d)/src/release-notes/rl-next.md
 	$(trace-gen) \
 		tmp="$$(mktemp -d)"; \
 		cp -r doc/manual "$$tmp"; \
@ -195,5 +225,3 @@ $(docdir)/manual/index.html: $(MANUAL_SRCS) $(d)/book.toml $(d)/anchors.jq $(d)/
 	@rm -rf $(DESTDIR)$(docdir)/manual
 	@mv $(DESTDIR)$(docdir)/manual.tmp/html $(DESTDIR)$(docdir)/manual
 	@rm -rf $(DESTDIR)$(docdir)/manual.tmp
-
-endif
--- a/doc/manual/redirects.js
+++ b/doc/manual/redirects.js
@ -1,7 +1,9 @@
-// redirect rules for anchors ensure backwards compatibility of URLs.
-// this must be done on the client side, as web servers do not see the anchor part of the URL.
+// redirect rules for URL fragments (client-side) to prevent link rot.
+// this must be done on the client side, as web servers do not see the fragment part of the URL.
+// it will only work with JavaScript enabled in the browser, but this is the best we can do here.
+// see ./_redirects for path redirects (client-side)

-// redirections are declared as follows:
+// redirects are declared as follows:
 // each entry has as its key a path matching the requested URL path, relative to the mdBook document root.
 //
 //     IMPORTANT: it must specify the full path with file name and suffix
@ -19,6 +21,7 @@ const redirects = {
    "chap-distributed-builds": "advanced-topics/distributed-builds.html",
    "chap-post-build-hook": "advanced-topics/post-build-hook.html",
    "chap-post-build-hook-caveats": "advanced-topics/post-build-hook.html#implementation-caveats",
+    "chap-writing-nix-expressions": "language/index.html",
    "part-command-ref": "command-ref/command-ref.html",
    "conf-allow-import-from-derivation": "command-ref/conf-file.html#conf-allow-import-from-derivation",
    "conf-allow-new-privileges": "command-ref/conf-file.html#conf-allow-new-privileges",
--- a/doc/manual/rl-next/allowed-uris-can-now-match-whole-schemes.md
+++ b/doc/manual/rl-next/allowed-uris-can-now-match-whole-schemes.md
@ -0,0 +1,7 @@
+---
+synopsis: Option `allowed-uris` can now match whole schemes in URIs without slashes
+prs: 9547
+---
+
+If a scheme, such as `github:` is specified in the `allowed-uris` option, all URIs starting with `github:` are allowed.
+Previously this only worked for schemes whose URIs used the `://` syntax.
--- a/doc/manual/rl-next/cgroup-stats.md
+++ b/doc/manual/rl-next/cgroup-stats.md
@ -0,0 +1,8 @@
+---
+synopsis: Include cgroup stats when building through the daemon
+prs: 9598
+---
+
+Nix now also reports cgroup statistics when building through the nix daemon and when doing remote builds using ssh-ng,
+if both sides of the connection are this version of Nix or newer. 
+
--- a/doc/manual/rl-next/config
+++ b/doc/manual/rl-next/config
@ -0,0 +1,2 @@
+organization: NixOS
+repository: nix
--- a/doc/manual/rl-next/drv-string-parse-hang.md
+++ b/doc/manual/rl-next/drv-string-parse-hang.md
@ -0,0 +1,6 @@
+---
+synopsis: Fix handling of truncated `.drv` files.
+prs: 9673
+---
+
+Previously a `.drv` that was truncated in the middle of a string would case nix to enter an infinite loop, eventually exhausting all memory and crashing.
--- a/doc/manual/rl-next/env-size-reduction.md
+++ b/doc/manual/rl-next/env-size-reduction.md
@ -0,0 +1,7 @@
+---
+synopsis: Reduce eval memory usage and wall time
+prs: 9658
+---
+
+Reduce the size of the `Env` struct used in the evaluator by a pointer, or 8 bytes on most modern machines.
+This reduces memory usage during eval by around 2% and wall time by around 3%.
--- a/doc/manual/rl-next/eval-system.md
+++ b/doc/manual/rl-next/eval-system.md
@ -0,0 +1,12 @@
+---
+synopsis: Add new `eval-system` setting
+prs: 4093
+---
+
+Add a new `eval-system` option.
+Unlike `system`, it just overrides the value of `builtins.currentSystem`.
+This is more useful than overriding `system`, because you can build these derivations on remote builders which can work on the given system.
+In contrast, `system` also effects scheduling which will cause Nix to build those derivations locally even if that doesn't make sense.
+
+`eval-system` only takes effect if it is non-empty.
+If empty (the default) `system` is used as before, so there is no breakage.
--- a/doc/manual/rl-next/git-fetcher.md
+++ b/doc/manual/rl-next/git-fetcher.md
@ -0,0 +1,18 @@
+---
+synopsis: "Nix now uses `libgit2` for Git fetching"
+prs:
+  - 9240
+  - 9241
+  - 9258
+  - 9480
+issues:
+  - 5313
+---
+
+Nix has built-in support for fetching sources from Git, during evaluation and locking; outside the sandbox.
+The existing implementation based on the Git CLI had issues regarding reproducibility and performance.
+
+Most of the original `fetchGit` behavior has been implemented using the `libgit2` library, which gives the fetcher fine-grained control.
+
+Known issues:
+- The `export-subst` behavior has not been reimplemented. [Partial](https://github.com/NixOS/nix/pull/9391#issuecomment-1872503447) support for this Git feature is feasible, but it did not make the release window.
--- a/doc/manual/rl-next/hash-format-nix32.md
+++ b/doc/manual/rl-next/hash-format-nix32.md
@ -0,0 +1,23 @@
+---
+synopsis: Rename hash format `base32` to `nix32`
+prs: 9452
+---
+
+Hash format `base32` was renamed to `nix32` since it used a special nix-specific character set for 
+[Base32](https://en.wikipedia.org/wiki/Base32).
+
+## Deprecation: Use `nix32` instead of `base32` as `toHashFormat`
+
+For the builtin `convertHash`, the `toHashFormat` parameter now accepts the same hash formats as the `--to`/`--from`
+parameters of the `nix hash conert` command: `"base16"`, `"nix32"`, `"base64"`, and `"sri"`. The former `"base32"` value
+remains as a deprecated alias for `"base32"`. Please convert your code from:
+
+```nix
+builtins.convertHash { inherit hash hashAlgo; toHashFormat = "base32";}
+```
+
+to
+
+```nix
+builtins.convertHash { inherit hash hashAlgo; toHashFormat = "nix32";}
+```
--- a/doc/manual/rl-next/ifd-eval-store.md
+++ b/doc/manual/rl-next/ifd-eval-store.md
@ -0,0 +1,8 @@
+---
+synopsis: import-from-derivation builds the derivation in the build store
+prs: 9661
+---
+
+When using `--eval-store`, `import`ing from a derivation will now result in the derivation being built on the build store, i.e. the store specified in the `store` Nix option.
+
+Because the resulting Nix expression must be copied back to the eval store in order to be imported, this requires the eval store to trust the build store's signatures.
--- a/doc/manual/rl-next/mounted-ssh-store.md
+++ b/doc/manual/rl-next/mounted-ssh-store.md
@ -0,0 +1,8 @@
+---
+synopsis: Mounted SSH Store
+issues: 7890
+prs: 7912
+---
+
+Introduced the store [`mounted-ssh-ng://`](@docroot@/command-ref/new-cli/nix3-help-stores.md).
+This store allows full access to a Nix store on a remote machine and additionally requires that the store be mounted in the local filesystem.
--- a/doc/manual/rl-next/nix-config-show.md
+++ b/doc/manual/rl-next/nix-config-show.md
@ -0,0 +1,7 @@
+---
+synopsis: Rename to `nix config show`
+issues: 7672
+prs: 9477
+---
+
+`nix show-config` was renamed to `nix config show`, and `nix doctor` was renamed to `nix config check`, to be more consistent with the rest of the command-line interface.
--- a/doc/manual/rl-next/nix-env-json-drv-path.md
+++ b/doc/manual/rl-next/nix-env-json-drv-path.md
@ -0,0 +1,6 @@
+---
+synopsis: Fix `nix-env --query --drv-path --json`
+prs: 9257
+---
+
+Fixed a bug where `nix-env --query` ignored `--drv-path` when `--json` was set.
--- a/doc/manual/rl-next/nix-hash-convert.md
+++ b/doc/manual/rl-next/nix-hash-convert.md
@ -0,0 +1,47 @@
+---
+synopsis: Add `nix hash convert`
+prs: 9452
+---
+
+New [`nix hash convert`](https://github.com/NixOS/nix/issues/8876) sub command with a fast track
+to stabilization! Examples:
+
+- Convert the hash to `nix32`.
+
+  ```bash
+  $ nix hash convert --hash-algo "sha1" --to nix32 "800d59cfcd3c05e900cb4e214be48f6b886a08df"
+  vw46m23bizj4n8afrc0fj19wrp7mj3c0
+  ```
+  `nix32` is a base32 encoding with a nix-specific character set.
+  Explicitly specify the hashing algorithm (optional with SRI hashes) but detect hash format by the length of the input
+  hash.
+- Convert the hash to the `sri` format that includes an algorithm specification:
+  ```bash
+  nix hash convert --hash-algo "sha1" "800d59cfcd3c05e900cb4e214be48f6b886a08df"
+  sha1-gA1Zz808BekAy04hS+SPa4hqCN8=
+  ```
+  or with an explicit `-to` format:
+  ```bash
+  nix hash convert --hash-algo "sha1" --to sri "800d59cfcd3c05e900cb4e214be48f6b886a08df"
+  sha1-gA1Zz808BekAy04hS+SPa4hqCN8=
+  ```
+- Assert the input format of the hash:
+  ```bash
+  nix hash convert --hash-algo "sha256" --from nix32 "ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0="
+  error: input hash 'ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0=' does not have the expected format '--from nix32'
+  nix hash convert --hash-algo "sha256" --from nix32 "1b8m03r63zqhnjf7l5wnldhh7c134ap5vpj0850ymkq1iyzicy5s"
+  sha256-ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0=
+  ```
+
+The `--to`/`--from`/`--hash-algo` parameters have context-sensitive auto-completion.
+
+## Related Deprecations
+
+The following commands are still available but will emit a deprecation warning. Please convert your code to
+`nix hash convert`:
+
+- `nix hash to-base16 $hash1 $hash2`: Use `nix hash convert --to base16 $hash1 $hash2` instead.
+- `nix hash to-base32 $hash1 $hash2`: Use `nix hash convert --to nix32 $hash1 $hash2` instead.
+- `nix hash to-base64 $hash1 $hash2`: Use `nix hash convert --to base64 $hash1 $hash2` instead.
+- `nix hash to-sri $hash1 $hash2`: : Use `nix hash convert --to sri $hash1 $hash2`
+  or even just `nix hash convert $hash1 $hash2` instead.
--- a/doc/manual/rl-next/nix-profile-names.md
+++ b/doc/manual/rl-next/nix-profile-names.md
@ -0,0 +1,8 @@
+---
+synopsis: "`nix profile` now allows referring to elements by human-readable name"
+prs: 8678
+---
+
+[`nix profile`](@docroot@/command-ref/new-cli/nix3-profile.md) now uses names to refer to installed packages when running [`list`](@docroot@/command-ref/new-cli/nix3-profile-list.md), [`remove`](@docroot@/command-ref/new-cli/nix3-profile-remove.md) or [`upgrade`](@docroot@/command-ref/new-cli/nix3-profile-upgrade.md) as opposed to indices. Profile element names are generated when a package is installed and remain the same until the package is removed.
+
+**Warning**: The `manifest.nix` file used to record the contents of profiles has changed. Nix will automatically upgrade profiles to the new version when you modify the profile. After that, the profile can no longer be used by older versions of Nix.
--- a/doc/manual/rl-next/nix-store-add.md
+++ b/doc/manual/rl-next/nix-store-add.md
@ -0,0 +1,7 @@
+---
+synopsis: Give `nix store add` a `--hash-algo` flag
+prs: 9809
+---
+
+Adds a missing feature that was present in the old CLI, and matches our
+plans to have similar flags for `nix hash convert` and `nix hash path`.
--- a/doc/manual/rl-next/source-positions-in-errors.md
+++ b/doc/manual/rl-next/source-positions-in-errors.md
@ -0,0 +1,42 @@
+---
+synopsis: Source locations are printed more consistently in errors
+issues: 561
+prs: 9555
+---
+
+Source location information is now included in error messages more
+consistently. Given this code:
+
+```nix
+let
+  attr = {foo = "bar";};
+  key = {};
+in
+  attr.${key}
+```
+
+Previously, Nix would show this unhelpful message when attempting to evaluate
+it:
+
+```
+error:
+       … while evaluating an attribute name
+
+       error: value is a set while a string was expected
+```
+
+Now, the error message displays where the problematic value was found:
+
+```
+error:
+       … while evaluating an attribute name
+
+         at bad.nix:4:11:
+
+            3|   key = {};
+            4| in attr.${key}
+             |           ^
+            5|
+
+       error: value is a set while a string was expected
+```
--- a/doc/manual/rl-next/stack-overflow-segfaults.md
+++ b/doc/manual/rl-next/stack-overflow-segfaults.md
@ -0,0 +1,32 @@
+---
+synopsis: Some stack overflow segfaults are fixed
+issues: 9616
+prs: 9617
+---
+
+The number of nested function calls has been restricted, to detect and report
+infinite function call recursions. The default maximum call depth is 10,000 and
+can be set with [the `max-call-depth`
+option](@docroot@/command-ref/conf-file.md#conf-max-call-depth).
+
+This fixes segfaults or the following unhelpful error message in many cases:
+
+    error: stack overflow (possible infinite recursion)
+
+Before:
+
+```
+$ nix-instantiate --eval --expr '(x: x x) (x: x x)'
+Segmentation fault: 11
+```
+
+After:
+
+```
+$ nix-instantiate --eval --expr '(x: x x) (x: x x)'
+error: stack overflow
+
+       at «string»:1:14:
+            1| (x: x x) (x: x x)
+             |              ^
+```
--- a/doc/manual/rl-next/with-error-reporting.md
+++ b/doc/manual/rl-next/with-error-reporting.md
@ -0,0 +1,31 @@
+---
+synopsis: Better error reporting for `with` expressions
+prs: 9658
+---
+
+`with` expressions using non-attrset values to resolve variables are now reported with proper positions.
+
+Previously an incorrect `with` expression would report no position at all, making it hard to determine where the error originated:
+
+```
+nix-repl> with 1; a  
+error:
+       … <borked>
+
+         at «none»:0: (source not available)
+
+       error: value is an integer while a set was expected
+```
+
+Now position information is preserved and reported as with most other errors:
+
+```
+nix-repl> with 1; a
+error:
+       … while evaluating the first subexpression of a with expression
+         at «string»:1:1:
+            1| with 1; a
+             | ^
+
+       error: value is an integer while a set was expected
+```
--- a/doc/manual/src/SUMMARY.md.in
+++ b/doc/manual/src/SUMMARY.md.in
@ -2,7 +2,7 @@

 - [Introduction](introduction.md)
 - [Quick Start](quick-start.md)
- [Installation](installation/installation.md)
+- [Installation](installation/index.md)
  - [Supported Platforms](installation/supported-platforms.md)
  - [Installing a Binary Distribution](installation/installing-binary.md)
  - [Installing Nix from Source](installation/installing-source.md)
@ -20,6 +20,8 @@
  - [File System Object](store/file-system-object.md)
  - [Store Object](store/store-object.md)
  - [Store Path](store/store-path.md)
+  - [Store Types](store/types/index.md)
+{{#include ./store/types/SUMMARY.md}}
 - [Nix Language](language/index.md)
  - [Data Types](language/values.md)
  - [Language Constructs](language/constructs.md)
@ -31,11 +33,11 @@
    - [Import From Derivation](language/import-from-derivation.md)
  - [Built-in Constants](language/builtin-constants.md)
  - [Built-in Functions](language/builtins.md)
- [Package Management](package-management/package-management.md)
+- [Package Management](package-management/index.md)
  - [Profiles](package-management/profiles.md)
  - [Garbage Collection](package-management/garbage-collection.md)
    - [Garbage Collector Roots](package-management/garbage-collector-roots.md)
- [Advanced Topics](advanced-topics/advanced-topics.md)
+- [Advanced Topics](advanced-topics/index.md)
  - [Sharing Packages Between Machines](package-management/sharing-packages.md)
    - [Serving a Nix store via HTTP](package-management/binary-cache-substituter.md)
    - [Copying Closures via SSH](package-management/copy-closure.md)
@ -45,7 +47,7 @@
  - [Tuning Cores and Jobs](advanced-topics/cores-vs-jobs.md)
  - [Verifying Build Reproducibility](advanced-topics/diff-hook.md)
  - [Using the `post-build-hook`](advanced-topics/post-build-hook.md)
- [Command Reference](command-ref/command-ref.md)
+- [Command Reference](command-ref/index.md)
  - [Common Options](command-ref/opt-common.md)
  - [Common Environment Variables](command-ref/env-common.md)
  - [Main Commands](command-ref/main-commands.md)
@ -102,19 +104,22 @@
    - [Channels](command-ref/files/channels.md)
    - [Default Nix expression](command-ref/files/default-nix-expression.md)
 - [Architecture and Design](architecture/architecture.md)
- [Protocols](protocols/protocols.md)
+- [JSON Formats](json/index.md)
+  - [Store Object Info](json/store-object-info.md)
+  - [Derivation](json/derivation.md)
+- [Protocols](protocols/index.md)
  - [Serving Tarball Flakes](protocols/tarball-fetcher.md)
  - [Derivation "ATerm" file format](protocols/derivation-aterm.md)
 - [Glossary](glossary.md)
- [Contributing](contributing/contributing.md)
+- [Contributing](contributing/index.md)
  - [Hacking](contributing/hacking.md)
  - [Testing](contributing/testing.md)
  - [Documentation](contributing/documentation.md)
  - [Experimental Features](contributing/experimental-features.md)
  - [CLI guideline](contributing/cli-guideline.md)
  - [C++ style guide](contributing/cxx.md)
- [Release Notes](release-notes/release-notes.md)
-  - [Release X.Y (202?-??-??)](release-notes/rl-next.md)
+- [Release Notes](release-notes/index.md)
+{{#include ./SUMMARY-rl-next.md}}
  - [Release 2.19 (2023-11-17)](release-notes/rl-2.19.md)
  - [Release 2.18 (2023-09-20)](release-notes/rl-2.18.md)
  - [Release 2.17 (2023-07-24)](release-notes/rl-2.17.md)
--- a/doc/manual/src/advanced-topics/advanced-topics.md
+++ b/doc/manual/src/advanced-topics/advanced-topics.md
--- a/doc/manual/src/architecture/architecture.md
+++ b/doc/manual/src/architecture/architecture.md
@ -52,7 +52,7 @@ The following [concept map] shows its main components (rectangles), the objects
                                            '---------------'
 ```

-At the top is the [command line interface](../command-ref/command-ref.md) that drives the underlying layers.
+At the top is the [command line interface](../command-ref/index.md) that drives the underlying layers.

 The [Nix language](../language/index.md) evaluator transforms Nix expressions into self-contained *build plans*, which are used to derive *build results* from referenced *build inputs*.

--- a/doc/manual/src/command-ref/command-ref.md
+++ b/doc/manual/src/command-ref/command-ref.md
--- a/doc/manual/src/command-ref/nix-instantiate.md
+++ b/doc/manual/src/command-ref/nix-instantiate.md
@ -35,13 +35,51 @@ standard input.

  - `--parse`\
    Just parse the input files, and print their abstract syntax trees on
-    standard output in ATerm format.
+    standard output as a Nix expression.

  - `--eval`\
    Just parse and evaluate the input files, and print the resulting
    values on standard output. No instantiation of store derivations
    takes place.

+    > **Warning**
+    >
+    > This option produces output which can be parsed as a Nix expression which
+    > will produce a different result than the input expression when evaluated.
+    > For example, these two Nix expressions print the same result despite
+    > having different meaning:
+    >
+    > ```console
+    > $ nix-instantiate --eval --expr '{ a = {}; }'
+    > { a = <CODE>; }
+    > $ nix-instantiate --eval --expr '{ a = <CODE>; }'
+    > { a = <CODE>; }
+    > ```
+    >
+    > For human-readable output, `nix eval` (experimental) is more informative:
+    >
+    > ```console
+    > $ nix-instantiate --eval --expr 'a: a'
+    > <LAMBDA>
+    > $ nix eval --expr 'a: a'
+    > «lambda @ «string»:1:1»
+    > ```
+    >
+    > For machine-readable output, the `--xml` option produces unambiguous
+    > output:
+    >
+    > ```console
+    > $ nix-instantiate --eval --xml --expr '{ foo = <CODE>; }'
+    > <?xml version='1.0' encoding='utf-8'?>
+    > <expr>
+    >   <attrs>
+    >     <attr column="3" line="1" name="foo">
+    >       <unevaluated />
+    >     </attr>
+    >   </attrs>
+    > </expr>
+    > ```
+
  - `--find-file`\
    Look up the given files in Nix’s search path (as specified by the
    `NIX_PATH` environment variable). If found, print the corresponding
@ -61,11 +99,11 @@ standard input.

  - `--json`\
    When used with `--eval`, print the resulting value as an JSON
-    representation of the abstract syntax tree rather than as an ATerm.
+    representation of the abstract syntax tree rather than as a Nix expression.

  - `--xml`\
    When used with `--eval`, print the resulting value as an XML
-    representation of the abstract syntax tree rather than as an ATerm.
+    representation of the abstract syntax tree rather than as a Nix expression.
    The schema is the same as that used by the [`toXML`
    built-in](../language/builtins.md).

@ -133,28 +171,24 @@ $ nix-instantiate --eval --xml --expr '1 + 2'
 The difference between non-strict and strict evaluation:

 ```console
-$ nix-instantiate --eval --xml --expr 'rec { x = "foo"; y = x; }'
-...
-  <attr name="x">
-    <string value="foo" />
-  </attr>
-  <attr name="y">
+$ nix-instantiate --eval --xml --expr '{ x = {}; }'
+<?xml version='1.0' encoding='utf-8'?>
+<expr>
+  <attrs>
+    <attr column="3" line="1" name="x">
      <unevaluated />
    </attr>
-...
-```
+  </attrs>
+</expr>

-Note that `y` is left unevaluated (the XML representation doesn’t
-attempt to show non-normal forms).
-
-```console
-$ nix-instantiate --eval --xml --strict --expr 'rec { x = "foo"; y = x; }'
-...
-  <attr name="x">
-    <string value="foo" />
+$ nix-instantiate --eval --xml --strict --expr '{ x = {}; }'
+<?xml version='1.0' encoding='utf-8'?>
+<expr>
+  <attrs>
+    <attr column="3" line="1" name="x">
+      <attrs>
+      </attrs>
    </attr>
-  <attr name="y">
-    <string value="foo" />
-  </attr>
-...
+  </attrs>
+</expr>
 ```
--- a/doc/manual/src/contributing/cli-guideline.md
+++ b/doc/manual/src/contributing/cli-guideline.md
@ -87,7 +87,7 @@ impacted the most by bad user experience.
      and [aligning of text](#text-alignment).
    - [Autocomplete](#shell-completion) of options.

-  Examples of such commands: `nix doctor`, `nix edit`, `nix eval`, ...
+  Examples of such commands: `nix edit`, `nix eval`, ...

 - **Utility and scripting commands**

@ -426,7 +426,7 @@ This leads to the following guidelines:
 ### Examples


-This is bad, because all keys must be assumed to be store implementations:
+This is bad, because all keys must be assumed to be store types:

 ```json
 {
--- a/doc/manual/src/contributing/documentation.md
+++ b/doc/manual/src/contributing/documentation.md
@ -172,7 +172,7 @@ Please observe these guidelines to ease reviews:
  > ```
  ````

-  Highlight syntax definiions as such, using [EBNF](https://en.wikipedia.org/wiki/Extended_Backus%E2%80%93Naur_form) notation:
+  Highlight syntax definitions as such, using [EBNF](https://en.wikipedia.org/wiki/Extended_Backus%E2%80%93Naur_form) notation:

  ````
  > **Syntax**
--- a/doc/manual/src/contributing/hacking.md
+++ b/doc/manual/src/contributing/hacking.md
@ -10,7 +10,7 @@ $ cd nix

 The following instructions assume you already have some version of Nix installed locally, so that you can use it to set up the development environment. If you don't have it installed, follow the [installation instructions].

-[installation instructions]: ../installation/installation.md
+[installation instructions]: ../installation/index.md

 ## Building Nix with flakes

@ -31,7 +31,7 @@ This shell also adds `./outputs/bin/nix` to your `$PATH` so you can run `nix` im
 To get a shell with one of the other [supported compilation environments](#compilation-environments):

 ```console
-$ nix develop .#native-clang11StdenvPackages
+$ nix develop .#native-clangStdenvPackages
 ```

 > **Note**
@ -51,11 +51,14 @@ To install it in `$(pwd)/outputs` and test it:

 ```console
 [nix-shell]$ make install
-[nix-shell]$ make installcheck -j $NIX_BUILD_CORES
+[nix-shell]$ make installcheck check -j $NIX_BUILD_CORES
 [nix-shell]$ nix --version
 nix (Nix) 2.12
 ```

+For more information on running and filtering tests, see
+[`testing.md`](./testing.md).
+
 To build a release version of Nix for the current operating system and CPU architecture:

 ```console
@ -75,7 +78,7 @@ $ nix-shell
 To get a shell with one of the other [supported compilation environments](#compilation-environments):

 ```console
-$ nix-shell --attr devShells.x86_64-linux.native-clang11StdenvPackages
+$ nix-shell --attr devShells.x86_64-linux.native-clangStdenvPackages
 ```

 > **Note**
@ -108,6 +111,26 @@ $ nix-build

 You can also build Nix for one of the [supported platforms](#platforms).

+## Makefile variables
+
+You may need `profiledir=$out/etc/profile.d` and `sysconfdir=$out/etc` to run `make install`.
+
+Run `make` with [`-e` / `--environment-overrides`](https://www.gnu.org/software/make/manual/make.html#index-_002de) to allow environment variables to override `Makefile` variables:
+
+- `ENABLE_BUILD=yes` to enable building the C++ code.
+- `ENABLE_DOC_GEN=yes` to enable building the documentation (manual, man pages, etc.).
+
+  The docs can take a while to build, so you may want to disable this for local development.
+- `ENABLE_FUNCTIONAL_TESTS=yes` to enable building the functional tests.
+- `ENABLE_UNIT_TESTS=yes` to enable building the unit tests.
+- `OPTIMIZE=1` to enable optimizations.
+- `libraries=libutil programs=` to only build a specific library.
+
+  This will fail in the linking phase if the other libraries haven't been built, but is useful for checking types.
+- `libraries= programs=nix` to only build a specific program.
+
+  This will not work in general, because the programs need the libraries.
+
 ## Platforms

 Nix can be built for various platforms, as specified in [`flake.nix`]:
@ -146,6 +169,31 @@ $ nix build .#packages.aarch64-linux.default
 Cross-compiled builds are available for ARMv6 (`armv6l-linux`) and ARMv7 (`armv7l-linux`).
 Add more [system types](#system-type) to `crossSystems` in `flake.nix` to bootstrap Nix on unsupported platforms.

+### Building for multiple platforms at once
+
+It is useful to perform multiple cross and native builds on the same source tree,
+for example to ensure that better support for one platform doesn't break the build for another.
+In order to facilitate this, Nix has some support for being built out of tree – that is, placing build artefacts in a different directory than the source code:
+
+1. Create a directory for the build, e.g.
+
+   ```bash
+   mkdir build
+   ```
+
+2. Run the configure script from that directory, e.g.
+
+   ```bash
+   cd build
+   ../configure <configure flags>
+   ```
+
+3. Run make from the source directory, but with the build directory specified, e.g.
+
+   ```bash
+   make builddir=build <make flags>
+   ```
+
 ## System type

 Nix uses a string with he following format to identify the *system type* or *platform* it runs on:
@ -220,3 +268,82 @@ Configure your editor to use the `clangd` from the shell, either by running it i
 > For some editors (e.g. Visual Studio Code), you may need to install a [special extension](https://open-vsx.org/extension/llvm-vs-code-extensions/vscode-clangd) for the editor to interact with `clangd`.
 > Some other editors (e.g. Emacs, Vim) need a plugin to support LSP servers in general (e.g. [lsp-mode](https://github.com/emacs-lsp/lsp-mode) for Emacs and [vim-lsp](https://github.com/prabirshrestha/vim-lsp) for vim).
 > Editor-specific setup is typically opinionated, so we will not cover it here in more detail.
+
+## Add a release note
+
+`doc/manual/rl-next` contains release notes entries for all unreleased changes.
+
+User-visible changes should come with a release note.
+
+### Add an entry
+
+Here's what a complete entry looks like. The file name is not incorporated in the document.
+
+```
+---
+synopsis: Basically a title
+issues: 1234
+prs: 1238
+---
+
+Here's one or more paragraphs that describe the change.
+
+- It's markdown
+- Add references to the manual using @docroot@
+```
+
+Significant changes should add the following header, which moves them to the top.
+
+```
+significance: significant
+```
+
+<!-- Keep an eye on https://codeberg.org/fgaz/changelog-d/issues/1 -->
+See also the [format documentation](https://github.com/haskell/cabal/blob/master/CONTRIBUTING.md#changelog).
+
+### Build process
+
+Releases have a precomputed `rl-MAJOR.MINOR.md`, and no `rl-next.md`.
+Set `buildUnreleasedNotes = true;` in `flake.nix` to build the release notes on the fly.
+
+## Branches
+
+- [`master`](https://github.com/NixOS/nix/commits/master)
+
+  The main development branch. All changes are approved and merged here.
+  When developing a change, create a branch based on the latest `master`.
+
+  Maintainers try to [keep it in a release-worthy state](#reverting).
+
+- [`maintenance-*.*`](https://github.com/NixOS/nix/branches/all?query=maintenance)
+
+  These branches are the subject of backports only, and are
+  also [kept](#reverting) in a release-worthy state.
+
+  See [`maintainers/backporting.md`](https://github.com/NixOS/nix/blob/master/maintainers/backporting.md)
+
+- [`latest-release`](https://github.com/NixOS/nix/tree/latest-release)
+
+  The latest patch release of the latest minor version.
+
+  See [`maintainers/release-process.md`](https://github.com/NixOS/nix/blob/master/maintainers/release-process.md)
+
+- [`backport-*-to-*`](https://github.com/NixOS/nix/branches/all?query=backport)
+
+  Generally branches created by the backport action.
+
+  See [`maintainers/backporting.md`](https://github.com/NixOS/nix/blob/master/maintainers/backporting.md)
+
+- [_other_](https://github.com/NixOS/nix/branches/all)
+
+  Branches that do not conform to the above patterns should be feature branches.
+
+## Reverting
+
+If a change turns out to be merged by mistake, or contain a regression, it may be reverted.
+A revert is not a rejection of the contribution, but merely part of an effective development process.
+It makes sure that development keeps running smoothly, with minimal uncertainty, and less overhead.
+If maintainers have to worry too much about avoiding reverts, they would not be able to merge as much.
+By embracing reverts as a good part of the development process, everyone wins.
+
+However, taking a step back may be frustrating, so maintainers will be extra supportive on the next try.
--- a/doc/manual/src/contributing/contributing.md
+++ b/doc/manual/src/contributing/contributing.md
--- a/doc/manual/src/contributing/testing.md
+++ b/doc/manual/src/contributing/testing.md
@ -20,6 +20,7 @@ The unit tests are defined using the [googletest] and [rapidcheck] frameworks.

 [googletest]: https://google.github.io/googletest/
 [rapidcheck]: https://github.com/emil-e/rapidcheck
+[property testing]: https://en.wikipedia.org/wiki/Property_testing

 ### Source and header layout

@ -28,39 +29,55 @@ The unit tests are defined using the [googletest] and [rapidcheck] frameworks.
 > ```
 > src
 > ├── libexpr
+> │   ├── local.mk
 > │   ├── value/context.hh
 > │   ├── value/context.cc
-> │   │
-> │   …
->     └── tests
-> │       ├── value/context.hh
-> │       ├── value/context.cc
-> │       │
 > │   …
 > │
-> ├── unit-test-data
-> │   ├── libstore
-> │   │   ├── worker-protocol/content-address.bin
+> ├── tests
+> │   │
+> │   …
+> │   └── unit
+> │       ├── libutil
+> │       │   ├── local.mk
 > │       │   …
+> │       │   └── data
+> │       │       ├── git/tree.txt
+> │       │       …
+> │       │
+> │       ├── libexpr-support
+> │       │   ├── local.mk
+> │       │   └── tests
+> │       │       ├── value/context.hh
+> │       │       ├── value/context.cc
+> │       │       …
+> │       │
+> │       ├── libexpr
+> │       …   ├── local.mk
+> │           ├── value/context.cc
 > │           …
 > …
 > ```

-The unit tests for each Nix library (`libnixexpr`, `libnixstore`, etc..) live inside a directory `src/${library_shortname}/tests` within the directory for the library (`src/${library_shortname}`).
+The tests for each Nix library (`libnixexpr`, `libnixstore`, etc..) live inside a directory `tests/unit/${library_name_without-nix}`.
+Given a interface (header) and implementation pair in the original library, say, `src/libexpr/value/context.{hh,cc}`, we write tests for it in `tests/unit/libexpr/tests/value/context.cc`, and (possibly) declare/define additional interfaces for testing purposes in `tests/unit/libexpr-support/tests/value/context.{hh,cc}`.

-The data is in `unit-test-data`, with one subdir per library, with the same name as where the code goes.
-For example, `libnixstore` code is in `src/libstore`, and its test data is in `unit-test-data/libstore`.
-The path to the `unit-test-data` directory is passed to the unit test executable with the environment variable `_NIX_TEST_UNIT_DATA`.
+Data for unit tests is stored in a `data` subdir of the directory for each unit test executable.
+For example, `libnixstore` code is in `src/libstore`, and its test data is in `tests/unit/libstore/data`.
+The path to the `tests/unit/data` directory is passed to the unit test executable with the environment variable `_NIX_TEST_UNIT_DATA`.
+Note that each executable only gets the data for its tests.

-> **Note**
-> Due to the way googletest works, downstream unit test executables will actually include and re-run upstream library tests.
-> Therefore it is important that the same value for `_NIX_TEST_UNIT_DATA` be used with the tests for each library.
-> That is why we have the test data nested within a single `unit-test-data` directory.
+The unit test libraries are in `tests/unit/${library_name_without-nix}-lib`.
+All headers are in a `tests` subdirectory so they are included with `#include "tests/"`.
+
+The use of all these separate directories for the unit tests might seem inconvenient, as for example the tests are not "right next to" the part of the code they are testing.
+But organizing the tests this way has one big benefit:
+there is no risk of any build-system wildcards for the library accidentally picking up test code that should not built and installed as part of the library.

 ### Running tests

 You can run the whole testsuite with `make check`, or the tests for a specific component with `make libfoo-tests_RUN`.
-Finer-grained filtering is also possible using the [--gtest_filter](https://google.github.io/googletest/advanced.html#running-a-subset-of-the-tests) command-line option, or the `GTEST_FILTER` environment variable.
+Finer-grained filtering is also possible using the [--gtest_filter](https://google.github.io/googletest/advanced.html#running-a-subset-of-the-tests) command-line option, or the `GTEST_FILTER` environment variable, e.g. `GTEST_FILTER='ErrorTraceTest.*' make check`.

 ### Characterisation testing { #characaterisation-testing-unit }

@ -69,7 +86,7 @@ See [functional characterisation testing](#characterisation-testing-functional)
 Like with the functional characterisation, `_NIX_TEST_ACCEPT=1` is also used.
 For example:
 ```shell-session
-$ _NIX_TEST_ACCEPT=1 make libstore-tests-exe_RUN
+$ _NIX_TEST_ACCEPT=1 make libstore-tests_RUN
 ...
 [  SKIPPED ] WorkerProtoTest.string_read
 [  SKIPPED ] WorkerProtoTest.string_write
@ -80,6 +97,18 @@ $ _NIX_TEST_ACCEPT=1 make libstore-tests-exe_RUN
 will regenerate the "golden master" expected result for the `libnixstore` characterisation tests.
 The characterisation tests will mark themselves "skipped" since they regenerated the expected result instead of actually testing anything.

+### Unit test support libraries
+
+There are headers and code which are not just used to test the library in question, but also downstream libraries.
+For example, we do [property testing] with the [rapidcheck] library.
+This requires writing `Arbitrary` "instances", which are used to describe how to generate values of a given type for the sake of running property tests.
+Because types contain other types, `Arbitrary` "instances" for some type are not just useful for testing that type, but also any other type that contains it.
+Downstream types frequently contain upstream types, so it is very important that we share arbitrary instances so that downstream libraries' property tests can also use them.
+
+It is important that these testing libraries don't contain any actual tests themselves.
+On some platforms they would be run as part of every test executable that uses them, which is redundant.
+On other platforms they wouldn't be run at all.
+
 ## Functional tests

 The functional tests reside under the `tests/functional` directory and are listed in `tests/functional/local.mk`.
--- a/doc/manual/src/glossary.md
+++ b/doc/manual/src/glossary.md
@ -3,10 +3,10 @@
 - [derivation]{#gloss-derivation}

  A description of a build task. The result of a derivation is a
-  store object. Derivations are typically specified in Nix expressions
+  store object. Derivations declared in Nix expressions are specified
  using the [`derivation` primitive](./language/derivations.md). These are
  translated into low-level *store derivations* (implicitly by
-  `nix-env` and `nix-build`, or explicitly by `nix-instantiate`).
+  `nix-build`, or explicitly by `nix-instantiate`).

  [derivation]: #gloss-derivation

@ -14,6 +14,7 @@

  A [derivation] represented as a `.drv` file in the [store].
  It has a [store path], like any [store object].
+  It is the [instantiated][instantiate] form of a derivation.

  Example: `/nix/store/g946hcz4c8mdvq2g8vxx42z51qb71rvp-git-2.38.1.drv`

@ -23,9 +24,9 @@

 - [instantiate]{#gloss-instantiate}, instantiation

-  Translate a [derivation] into a [store derivation].
+  Save an evaluated [derivation] as a [store derivation] in the Nix [store].

-  See [`nix-instantiate`](./command-ref/nix-instantiate.md).
+  See [`nix-instantiate`](./command-ref/nix-instantiate.md), which produces a store derivation from a Nix expression that evaluates to a derivation.

  [instantiate]: #gloss-instantiate

@ -66,7 +67,7 @@

  From the perspective of the location where Nix is invoked, the Nix store can be  referred to _local_ or _remote_.
  Only a [local store]{#gloss-local-store} exposes a location in the file system of the machine where Nix is invoked that allows access to store objects, typically `/nix/store`.
-  Local stores can be used for building [derivations](#derivation).
+  Local stores can be used for building [derivations](#gloss-derivation).
  See [Local Store](@docroot@/command-ref/new-cli/nix3-help-stores.md#local-store) for details.

  [store]: #gloss-store
@ -126,7 +127,7 @@
  non-[fixed-output](#gloss-fixed-output-derivation)
  derivation.

- [output-addressed store object]{#gloss-output-addressed-store-object}
+- [content-addressed store object]{#gloss-content-addressed-store-object}

  A [store object] whose [store path] is determined by its contents.
  This includes derivations, the outputs of [content-addressed derivations](#gloss-content-addressed-derivation), and the outputs of [fixed-output derivations](#gloss-fixed-output-derivation).
@ -166,11 +167,13 @@

 - [Nix expression]{#gloss-nix-expression}

-  A high-level description of software packages and compositions
+  1. Commonly, a high-level description of software packages and compositions
    thereof. Deploying software using Nix entails writing Nix
-  expressions for your packages. Nix expressions are translated to
-  derivations that are stored in the Nix store. These derivations can
-  then be built.
+    expressions for your packages. Nix expressions specify [derivations][derivation],
+    which are [instantiated][instantiate] into the Nix store as [store derivations][store derivation].
+    These derivations can then be [realised][realise] to produce [outputs][output].
+
+  2. A syntactically valid use of the [Nix language]. For example, the contents of a `.nix` file form an expression.

 - [reference]{#gloss-reference}

@ -222,6 +225,9 @@

  The [store derivation] that produced an [output path].

+  The deriver for an output path can be queried with the `--deriver` option to
+  [`nix-store --query`](@docroot@/command-ref/nix-store/query.md).
+
 - [validity]{#gloss-validity}

  A store path is valid if all [store object]s in its [closure] can be read from the [store].
@ -266,6 +272,21 @@

  The epsilon symbol. In the context of a package, this means the version is empty. More precisely, the derivation does not have a version attribute.

+- [package]{#package}
+
+  1. A software package; a collection of files and other data.
+
+  2. A [package attribute set].
+
+- [package attribute set]{#package-attribute-set}
+
+  An [attribute set] containing the attribute `type = "derivation";` (derivation for historical reasons), as well as other attributes, such as
+  - attributes that refer to the files of a [package], typically in the form of [derivation outputs](#output),
+  - attributes that declare something about how the package is supposed to be installed or used,
+  - other metadata or arbitrary attributes.
+
+  [package attribute set]: #package-attribute-set
+
 - [string interpolation]{#gloss-string-interpolation}

  Expanding expressions enclosed in `${ }` within a [string], [path], or [attribute name].
@ -282,3 +303,6 @@
  These flags are enabled or disabled with the [`experimental-features`](./command-ref/conf-file.html#conf-experimental-features) setting.

  See the contribution guide on the [purpose and lifecycle of experimental feaures](@docroot@/contributing/experimental-features.md).
+
+
+[Nix language]: ./language/index.md
--- a/doc/manual/src/installation/installation.md
+++ b/doc/manual/src/installation/installation.md
--- a/doc/manual/src/installation/installing-binary.md
+++ b/doc/manual/src/installation/installing-binary.md
@ -1,26 +1,60 @@
 # Installing a Binary Distribution

-The easiest way to install Nix is to run the following command:
+To install the latest version Nix, run the following command:

 ```console
 $ curl -L https://nixos.org/nix/install | sh
 ```

-This will run the installer interactively (causing it to explain what
-it is doing more explicitly), and perform the default "type" of install
-for your platform:
- single-user on Linux
- multi-user on macOS
+This performs the default type of installation for your platform:

-  > **Notes on read-only filesystem root in macOS 10.15 Catalina +**
-  >
-  > - It took some time to support this cleanly. You may see posts,
-  >   examples, and tutorials using obsolete workarounds.
-  > - Supporting it cleanly made macOS installs too complex to qualify
-  >   as single-user, so this type is no longer supported on macOS.
+- [Multi-user](#multi-user-installation):
+  - Linux with systemd and without SELinux
+  - macOS
+- [Single-user](#single-user-installation):
+  - Linux without systemd
+  - Linux with SELinux

-We recommend the multi-user install if it supports your platform and
-you can authenticate with `sudo`.
+We recommend the multi-user installation if it supports your platform and you can authenticate with `sudo`.
+
+The installer can configured with various command line arguments and environment variables.
+To show available command line flags:
+
+```console
+$ curl -L https://nixos.org/nix/install | sh -s -- --help
+```
+
+To check what it does and how it can be customised further, [download and edit the second-stage installation script](#installing-from-a-binary-tarball).
+
+# Installing a pinned Nix version from a URL
+
+Version-specific installation URLs for all Nix versions since 1.11.16 can be found at [releases.nixos.org](https://releases.nixos.org/?prefix=nix/).
+The directory for each version contains the corresponding SHA-256 hash.
+
+All installation scripts are invoked the same way:
+
+```console
+$ export VERSION=2.19.2 
+$ curl -L https://releases.nixos.org/nix/nix-$VERSION/install | sh
+```
+
+# Multi User Installation
+
+The multi-user Nix installation creates system users and a system service for the Nix daemon.
+
+Supported systems:
+
+- Linux running systemd, with SELinux disabled
+- macOS
+
+To explicitly instruct the installer to perform a multi-user installation on your system:
+
+```console
+$ curl -L https://nixos.org/nix/install | sh -s -- --daemon
+```
+
+You can run this under your usual user account or `root`.
+The script will invoke `sudo` as needed.

 # Single User Installation

@ -30,60 +64,48 @@ To explicitly select a single-user installation on your system:
 $ curl -L https://nixos.org/nix/install | sh -s -- --no-daemon
 ```

-This will perform a single-user installation of Nix, meaning that `/nix`
-is owned by the invoking user. You can run this under your usual user
-account or root. The script will invoke `sudo` to create `/nix`
-if it doesn’t already exist. If you don’t have `sudo`, you should
-manually create `/nix` first as root, e.g.:
+In a single-user installation, `/nix` is owned by the invoking user.
+The script will invoke `sudo` to create `/nix` if it doesn’t already exist.
+If you don’t have `sudo`, manually create `/nix` as `root`:

 ```console
-$ mkdir /nix
-$ chown alice /nix
+$ su root
+# mkdir /nix
+# chown alice /nix
 ```

-The install script will modify the first writable file from amongst
-`.bash_profile`, `.bash_login` and `.profile` to source
-`~/.nix-profile/etc/profile.d/nix.sh`. You can set the
-`NIX_INSTALLER_NO_MODIFY_PROFILE` environment variable before executing
-the install script to disable this behaviour.
+# Installing from a binary tarball

-# Multi User Installation
+You can also download a binary tarball that contains Nix and all its dependencies:
+- Choose a [version](https://releases.nixos.org/?prefix=nix/) and [system type](../contributing/hacking.md#platforms)
+- Download and unpack the tarball
+- Run the installer

-The multi-user Nix installation creates system users, and a system
-service for the Nix daemon.
-
-**Supported Systems**
- Linux running systemd, with SELinux disabled
- macOS
-
-You can instruct the installer to perform a multi-user installation on
-your system:
-
-```console
-$ curl -L https://nixos.org/nix/install | sh -s -- --daemon
-```
-
-The multi-user installation of Nix will create build users between the
-user IDs 30001 and 30032, and a group with the group ID 30000. You
-can run this under your usual user account or root. The script
-will invoke `sudo` as needed.
-
-> **Note**
+> **Example**
 >
-> If you need Nix to use a different group ID or user ID set, you will
-> have to download the tarball manually and [edit the install
-> script](#installing-from-a-binary-tarball).
+> ```console
+> $ pushd $(mktemp -d)
+> $ export VERSION=2.19.2
+> $ export SYSTEM=x86_64-linux
+> $ curl -LO https://releases.nixos.org/nix/nix-$VERSION/nix-$VERSION-$SYSTEM.tar.xz
+> $ tar xfj nix-$VERSION-$SYSTEM.tar.xz
+> $ cd nix-$VERSION-$SYSTEM
+> $ ./install
+> $ popd
+> ```

-The installer will modify `/etc/bashrc`, and `/etc/zshrc` if they exist.
-The installer will first back up these files with a `.backup-before-nix`
-extension. The installer will also create `/etc/profile.d/nix.sh`.
+The installer can be customised with the environment variables declared in the file named `install-multi-user`.
+
+## Native packages for Linux distributions
+
+The Nix community maintains installers for some Linux distributions in their native packaging format(https://nix-community.github.io/nix-installers/).

 # macOS Installation

+<!-- anchors to catch existing links -->
 []{#sect-macos-installation-change-store-prefix}[]{#sect-macos-installation-encrypted-volume}[]{#sect-macos-installation-symlink}[]{#sect-macos-installation-recommended-notes}
-<!-- Note: anchors above to catch permalinks to old explanations -->

-We believe we have ironed out how to cleanly support the read-only root
+We believe we have ironed out how to cleanly support the read-only root file system
 on modern macOS. New installs will do this automatically.

 This section previously detailed the situation, options, and trade-offs,
@ -126,33 +148,3 @@ this to run the installer, but it may help if you run into trouble:
  boot process to avoid problems loading or restoring any programs that
  need access to your Nix store

-# Installing a pinned Nix version from a URL
-
-Version-specific installation URLs for all Nix versions
-since 1.11.16 can be found at [releases.nixos.org](https://releases.nixos.org/?prefix=nix/).
-The corresponding SHA-256 hash can be found in the directory for the given version.
-
-These install scripts can be used the same as usual:
-
-```console
-$ curl -L https://releases.nixos.org/nix/nix-<version>/install | sh
-```
-
-# Installing from a binary tarball
-
-You can also download a binary tarball that contains Nix and all its
-dependencies. (This is what the install script at
-<https://nixos.org/nix/install> does automatically.) You should unpack
-it somewhere (e.g. in `/tmp`), and then run the script named `install`
-inside the binary tarball:
-
-```console
-$ cd /tmp
-$ tar xfj nix-1.8-x86_64-darwin.tar.bz2
-$ cd nix-1.8-x86_64-darwin
-$ ./install
-```
-
-If you need to edit the multi-user installation script to use different
-group ID or a different user ID range, modify the variables set in the
-file named `install-multi-user`.
--- a/doc/manual/src/installation/prerequisites-source.md
+++ b/doc/manual/src/installation/prerequisites-source.md
@ -32,11 +32,15 @@
    your distribution does not provide it, please install it from
    <http://www.sqlite.org/>.

-  - The [Boehm garbage collector](http://www.hboehm.info/gc/) to reduce
-    the evaluator’s memory consumption (optional). To enable it, install
+  - The [Boehm garbage collector (`bdw-gc`)](http://www.hboehm.info/gc/) to reduce
+    the evaluator’s memory consumption (optional).
+
+    To enable it, install
    `pkgconfig` and the Boehm garbage collector, and pass the flag
    `--enable-gc` to `configure`.

+    For `bdw-gc` <= 8.2.4 Nix needs a [small patch](https://github.com/NixOS/nix/blob/ac4d2e7b857acdfeac35ac8a592bdecee2d29838/boehmgc-traceable_allocator-public.diff) to be applied.
+
  - The `boost` library of version 1.66.0 or higher. It can be obtained
    from the official web site <https://www.boost.org/>.

@ -72,7 +76,7 @@
    This is an optional dependency and can be disabled
    by providing a `--disable-cpuid` to the `configure` script.

-  - Unless `./configure --disable-tests` is specified, GoogleTest (GTest) and
+  - Unless `./configure --disable-unit-tests` is specified, GoogleTest (GTest) and
    RapidCheck are required, which are available at
    <https://google.github.io/googletest/> and
    <https://github.com/emil-e/rapidcheck> respectively.
--- a/doc/manual/src/installation/upgrading.md
+++ b/doc/manual/src/installation/upgrading.md
@ -1,14 +1,40 @@
 # Upgrading Nix

-Multi-user Nix users on macOS can upgrade Nix by running: `sudo -i sh -c
-'nix-channel --update &&
-nix-env --install --attr nixpkgs.nix &&
-launchctl remove org.nixos.nix-daemon &&
-launchctl load /Library/LaunchDaemons/org.nixos.nix-daemon.plist'`
+> **Note**
+>
+> These upgrade instructions apply where Nix was installed following the [installation instructions in this manual](./index.md).

-Single-user installations of Nix should run this: `nix-channel --update;
-nix-env --install --attr nixpkgs.nix nixpkgs.cacert`
+Check which Nix version will be installed, for example from one of the [release channels](http://channels.nixos.org/) such as `nixpkgs-unstable`:

-Multi-user Nix users on Linux should run this with sudo: `nix-channel
--update; nix-env --install --attr nixpkgs.nix nixpkgs.cacert; systemctl
-daemon-reload; systemctl restart nix-daemon`
+```console
+$ nix-shell -p nix -I nixpkgs=channel:nixpkgs-unstable --run "nix --version"
+nix (Nix) 2.18.1
+```
+
+> **Warning**
+>
+> Writing to the [local store](@docroot@/store/types/local-store.md) with a newer version of Nix, for example by building derivations with [`nix-build`](@docroot@/command-ref/nix-build.md) or [`nix-store --realise`](@docroot@/command-ref/nix-store/realise.md), may change the database schema!
+> Reverting to an older version of Nix may therefore require purging the store database before it can be used.
+
+### Linux multi-user
+
+```console
+$ sudo su
+# nix-env --install --file '<nixpkgs>' --attr nix cacert -I nixpkgs=channel:nixpkgs-unstable
+# systemctl daemon-reload
+# systemctl restart nix-daemon
+```
+
+## macOS multi-user
+
+```console
+$ sudo nix-env --install --file '<nixpkgs>' --attr nix -I nixpkgs=channel:nixpkgs-unstable
+$ sudo launchctl remove org.nixos.nix-daemon
+$ sudo launchctl load /Library/LaunchDaemons/org.nixos.nix-daemon.plist
+```
+
+## Single-user all platforms
+
+```console
+$ nix-env --install --file '<nixpkgs>' --attr nix cacert -I nixpkgs=channel:nixpkgs-unstable
+```
--- a/doc/manual/src/json/derivation.md
+++ b/doc/manual/src/json/derivation.md
@ -0,0 +1,71 @@
+# Derivation JSON Format
+
+> **Warning**
+>
+> This JSON format is currently
+> [**experimental**](@docroot@/contributing/experimental-features.md#xp-feature-nix-command)
+> and subject to change.
+
+The JSON serialization of a
+[derivations](@docroot@/glossary.md#gloss-store-derivation)
+is a JSON object with the following fields:
+
+* `name`:
+  The name of the derivation.
+  This is used when calculating the store paths of the derivation's outputs.
+
+* `outputs`:
+  Information about the output paths of the derivation.
+  This is a JSON object with one member per output, where the key is the output name and the value is a JSON object with these fields:
+
+  * `path`: The output path.
+
+  * `hashAlgo`:
+    For fixed-output derivations, the hashing algorithm (e.g. `sha256`), optionally prefixed by `r:` if `hash` denotes a NAR hash rather than a flat file hash.
+
+  * `hash`:
+    For fixed-output derivations, the expected content hash in base-16.
+
+  > **Example**
+  >
+  > ```json
+  > "outputs": {
+  >   "out": {
+  >     "path": "/nix/store/2543j7c6jn75blc3drf4g5vhb1rhdq29-source",
+  >     "hashAlgo": "r:sha256",
+  >     "hash": "6fc80dcc62179dbc12fc0b5881275898f93444833d21b89dfe5f7fbcbb1d0d62"
+  >   }
+  > }
+  > ```
+
+* `inputSrcs`:
+  A list of store paths on which this derivation depends.
+
+* `inputDrvs`:
+  A JSON object specifying the derivations on which this derivation depends, and what outputs of those derivations.
+
+  > **Example**
+  >
+  > ```json
+  > "inputDrvs": {
+  >   "/nix/store/6lkh5yi7nlb7l6dr8fljlli5zfd9hq58-curl-7.73.0.drv": ["dev"],
+  >   "/nix/store/fn3kgnfzl5dzym26j8g907gq3kbm8bfh-unzip-6.0.drv": ["out"]
+  > }
+  > ```
+
+  specifies that this derivation depends on the `dev` output of `curl`, and the `out` output of `unzip`.
+
+* `system`:
+  The system type on which this derivation is to be built
+  (e.g. `x86_64-linux`).
+
+* `builder`:
+  The absolute path of the program to be executed to run the build.
+  Typically this is the `bash` shell
+  (e.g. `/nix/store/r3j288vpmczbl500w6zz89gyfa4nr0b1-bash-4.4-p23/bin/bash`).
+
+* `args`:
+  The command-line arguments passed to the `builder`.
+
+* `env`:
+  The environment passed to the `builder`.
--- a/doc/manual/src/json/store-object-info.md
+++ b/doc/manual/src/json/store-object-info.md
@ -0,0 +1,97 @@
+# Store object info JSON format
+
+> **Warning**
+>
+> This JSON format is currently
+> [**experimental**](@docroot@/contributing/experimental-features.md#xp-feature-nix-command)
+> and subject to change.
+
+Info about a [store object].
+
+* `path`:
+
+  [Store path][store path] to the given store object.
+
+* `narHash`:
+
+  Hash of the [file system object] part of the store object when serialized as a [Nix Archive](#gloss-nar).
+
+* `narSize`:
+
+  Size of the [file system object] part of the store object when serialized as a [Nix Archive](#gloss-nar).
+
+* `references`:
+
+  An array of [store paths][store path], possibly including this one.
+
+* `ca` (optional):
+
+  Content address of this store object's file system object, used to compute its store path.
+
+[store path]: @docroot@/glossary.md#gloss-store-path
+[file system object]: @docroot@/store/file-system-object.md
+
+## Impure fields
+
+These are not intrinsic properties of the store object.
+In other words, the same store object residing in different store could have different values for these properties.
+
+* `deriver` (optional):
+
+  The path to the [derivation] from which this store object is produced.
+
+  [derivation]: @docroot@/glossary.md#gloss-store-derivation
+
+* `registrationTime` (optional):
+
+  When this derivation was added to the store.
+
+* `ultimate` (optional):
+
+  Whether this store object is trusted because we built it ourselves, rather than substituted a build product from elsewhere.
+
+* `signatures` (optional):
+
+  Signatures claiming that this store object is what it claims to be.
+  Not relevant for [content-addressed] store objects,
+  but useful for [input-addressed] store objects.
+
+  [content-addressed]: @docroot@/glossary.md#gloss-content-addressed-store-object
+  [input-addressed]: @docroot@/glossary.md#gloss-input-addressed-store-object
+
+### `.narinfo` extra fields
+
+This meta data is specific to the "binary cache" family of Nix store types.
+This information is not intrinsic to the store object, but about how it is stored.
+
+* `url`:
+
+  Where to download a compressed archive of the file system objects of this store object.
+
+* `compression`:
+
+  The compression format that the archive is in.
+
+* `fileHash`:
+
+  A digest for the compressed archive itself, as opposed to the data contained within.
+
+* `fileSize`:
+
+  The size of the compressed archive itself.
+
+## Computed closure fields
+
+These fields are not stored at all, but computed by traverising the other other fields across all the store objects in a [closure].
+
+* `closureSize`:
+
+  The total size of the compressed archive itself for this object, and the compressed archive of every object in this object's [closure].
+
+### `.narinfo` extra fields
+
+* `closureSize`:
+
+  The total size of this store object and every other object in its [closure].
+
+[closure]: @docroot@/glossary.md#gloss-closure
--- a/doc/manual/src/language/advanced-attributes.md
+++ b/doc/manual/src/language/advanced-attributes.md
@ -257,29 +257,18 @@ Derivations can declare some infrequently used optional attributes.
    of the environment (typically, a few hundred kilobyte).

  - [`preferLocalBuild`]{#adv-attr-preferLocalBuild}\
-    If this attribute is set to `true` and [distributed building is
-    enabled](../advanced-topics/distributed-builds.md), then, if
-    possible, the derivation will be built locally instead of forwarded
-    to a remote machine. This is appropriate for trivial builders
-    where the cost of doing a download or remote build would exceed
-    the cost of building locally.
+    If this attribute is set to `true` and [distributed building is enabled](../advanced-topics/distributed-builds.md), then, if possible, the derivation will be built locally instead of being forwarded to a remote machine.
+    This is useful for derivations that are cheapest to build locally.

  - [`allowSubstitutes`]{#adv-attr-allowSubstitutes}\
-    If this attribute is set to `false`, then Nix will always build this
-    derivation; it will not try to substitute its outputs. This is
-    useful for very trivial derivations (such as `writeText` in Nixpkgs)
-    that are cheaper to build than to substitute from a binary cache.
+    If this attribute is set to `false`, then Nix will always build this derivation (locally or remotely); it will not try to substitute its outputs.
+    This is useful for derivations that are cheaper to build than to substitute.

-    You may disable the effects of this attibute by enabling the
-    `always-allow-substitutes` configuration option in Nix.
+    This attribute can be ignored by setting [`always-allow-substitutes`](@docroot@/command-ref/conf-file.md#conf-always-allow-substitutes) to `true`.

    > **Note**
    >
-    > You need to have a builder configured which satisfies the
-    > derivation’s `system` attribute, since the derivation cannot be
-    > substituted. Thus it is usually a good idea to align `system` with
-    > `builtins.currentSystem` when setting `allowSubstitutes` to
-    > `false`. For most trivial derivations this should be the case.
+    > If set to `false`, the [`builder`](./derivations.md#attr-builder) should be able to run on the system type specified in the [`system` attribute](./derivations.md#attr-system), since the derivation cannot be substituted.

  - [`__structuredAttrs`]{#adv-attr-structuredAttrs}\
    If the special attribute `__structuredAttrs` is set to `true`, the other derivation
--- a/doc/manual/src/language/derivations.md
+++ b/doc/manual/src/language/derivations.md
@ -274,7 +274,7 @@ The [`builder`](#attr-builder) is executed as follows:
    directory (typically, `/nix/store`).

  - `NIX_ATTRS_JSON_FILE` & `NIX_ATTRS_SH_FILE` if `__structuredAttrs`
-    is set to `true` for the dervation. A detailed explanation of this
+    is set to `true` for the derivation. A detailed explanation of this
    behavior can be found in the
    [section about structured attrs](./advanced-attributes.md#adv-attr-structuredAttrs).

--- a/doc/manual/src/language/values.md
+++ b/doc/manual/src/language/values.md
@ -116,6 +116,7 @@
  [store path]: ../glossary.md#gloss-store-path

  Paths can include [string interpolation] and can themselves be [interpolated in other expressions].
+
  [interpolated in other expressions]: ./string-interpolation.md#interpolated-expressions

  At least one slash (`/`) must appear *before* any interpolated expression for the result to be recognized as a path.
--- a/doc/manual/src/package-management/package-management.md
+++ b/doc/manual/src/package-management/package-management.md
--- a/doc/manual/src/protocols/protocols.md
+++ b/doc/manual/src/protocols/protocols.md
--- a/doc/manual/src/quick-start.md
+++ b/doc/manual/src/quick-start.md
@ -1,99 +1,43 @@
 # Quick Start

-This chapter is for impatient people who don't like reading
-documentation.  For more in-depth information you are kindly referred
-to subsequent chapters.
+This chapter is for impatient people who don't like reading documentation.
+For more in-depth information you are kindly referred to subsequent chapters.

-1. Install Nix by running the following:
+1. Install Nix:

   ```console
   $ curl -L https://nixos.org/nix/install | sh
   ```

   The install script will use `sudo`, so make sure you have sufficient rights.
-   On Linux, `--daemon` can be omitted for a single-user install.

-   For other installation methods, see [here](installation/installation.md).
+   For other installation methods, see the detailed [installation instructions](installation/index.md).

-1. See what installable packages are currently available in the
-   channel:
+1. Run software without installing it permanently:

   ```console
-   $ nix-env --query --available --attr-path
-   nixpkgs.docbook_xml_dtd_43                    docbook-xml-4.3
-   nixpkgs.docbook_xml_dtd_45                    docbook-xml-4.5
-   nixpkgs.firefox                               firefox-33.0.2
-   nixpkgs.hello                                 hello-2.9
-   nixpkgs.libxslt                               libxslt-1.1.28
-   …
+   $ nix-shell --packages cowsay lolcat
   ```

-1. Install some packages from the channel:
+   This downloads the specified packages with all their dependencies, and drops you into a Bash shell where the commands provided by those packages are present.
+   This will not affect your normal environment:

   ```console
-   $ nix-env --install --attr nixpkgs.hello
+   [nix-shell:~]$ cowsay Hello, Nix! | lolcat
   ```

-   This should download pre-built packages; it should not build them
-   locally (if it does, something went wrong).
-
-1. Test that they work:
+   Exiting the shell will make the programs disappear again:

   ```console
-   $ which hello
-   /home/eelco/.nix-profile/bin/hello
-   $ hello
-   Hello, world!
-   ```
-
-1. Uninstall a package:
-
-   ```console
-   $ nix-env --uninstall hello
-   ```
-
-1. You can also test a package without installing it:
-
-   ```console
-   $ nix-shell --packages hello
-   ```
-
-   This builds or downloads GNU Hello and its dependencies, then drops
-   you into a Bash shell where the `hello` command is present, all
-   without affecting your normal environment:
-
-   ```console
-   [nix-shell:~]$ hello
-   Hello, world!
-
   [nix-shell:~]$ exit
-
-   $ hello
-   hello: command not found
+   $ lolcat
+   lolcat: command not found
   ```

-1. To keep up-to-date with the channel, do:
+1. Search for more packages on <search.nixos.org> to try them out.
+
+1. Free up storage space:

   ```console
-   $ nix-channel --update nixpkgs
-   $ nix-env --upgrade '*'
-   ```
-
-   The latter command will upgrade each installed package for which
-   there is a “newer” version (as determined by comparing the version
-   numbers).
-
-1. If you're unhappy with the result of a `nix-env` action (e.g., an
-   upgraded package turned out not to work properly), you can go back:
-
-   ```console
-   $ nix-env --rollback
-   ```
-
-1. You should periodically run the Nix garbage collector to get rid of
-   unused packages, since uninstalls or upgrades don't actually delete
-   them:
-
-   ```console
-   $ nix-collect-garbage --delete-old
+   $ nix-collect-garbage
   ```
--- a/doc/manual/src/release-notes/release-notes.md
+++ b/doc/manual/src/release-notes/release-notes.md
--- a/doc/manual/src/release-notes/rl-2.19.md
+++ b/doc/manual/src/release-notes/rl-2.19.md
@ -18,7 +18,7 @@
 - `nix-shell` shebang lines now support single-quoted arguments.

 - `builtins.fetchTree` is now its own experimental feature, [`fetch-tree`](@docroot@/contributing/experimental-features.md#xp-fetch-tree).
-  As described in the documentation for that feature, this is because we anticipate polishing it and then stabilizing it before the rest of flakes.
+  This allows stabilising it independently of the rest of what is encompassed by [`flakes`](@docroot@/contributing/experimental-features.md#xp-fetch-tree).

 - The interface for creating and updating lock files has been overhauled:

--- a/doc/manual/src/release-notes/rl-next.md
+++ b/doc/manual/src/release-notes/rl-next.md
@ -1,2 +0,0 @@
-# Release X.Y (202?-??-??)
-
--- a/doc/manual/src/store/index.md
+++ b/doc/manual/src/store/index.md
@ -2,4 +2,4 @@

 The *Nix store* is an abstraction to store immutable file system data (such as software packages) that can have dependencies on other such data.

-There are multiple implementations of Nix stores with different capabilities, such as the actual filesystem (`/nix/store`) or binary caches.
+There are [multiple types of Nix stores](./types/index.md) with different capabilities, such as the default one on the [local filesystem](./types/local-store.md) (`/nix/store`) or [binary caches](./types/http-binary-cache-store.md).
--- a/doc/manual/src/store/types/index.md.in
+++ b/doc/manual/src/store/types/index.md.in
@ -1,6 +1,6 @@
-R"(
+Nix supports different types of stores:

-Nix supports different types of stores. These are described below.
+@store-types@

 ## Store URL format

@ -29,18 +29,15 @@ supported settings for each store type are documented below.
 The special store URL `auto` causes Nix to automatically select a
 store as follows:

-* Use the [local store](#local-store) `/nix/store` if `/nix/var/nix`
+* Use the [local store](./local-store.md) `/nix/store` if `/nix/var/nix`
  is writable by the current user.

 * Otherwise, if `/nix/var/nix/daemon-socket/socket` exists, [connect
-  to the Nix daemon listening on that socket](#local-daemon-store).
+  to the Nix daemon listening on that socket](./local-daemon-store.md).

-* Otherwise, on Linux only, use the [local chroot store](#local-store)
+* Otherwise, on Linux only, use the [local chroot store](./local-store.md)
  `~/.local/share/nix/root`, which will be created automatically if it
  does not exist.

-* Otherwise, use the [local store](#local-store) `/nix/store`.
+* Otherwise, use the [local store](./local-store.md) `/nix/store`.

-@stores@
-
-)"
--- a/doc/manual/utils.nix
+++ b/doc/manual/utils.nix
@ -1,5 +1,11 @@
 with builtins;

+let
+  lowerChars = stringToCharacters "abcdefghijklmnopqrstuvwxyz";
+  upperChars = stringToCharacters "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+  stringToCharacters = s: genList (p: substring p 1 s) (stringLength s);
+in
+
 rec {
  splitLines = s: filter (x: !isList x) (split "\n" s);

@ -18,6 +24,8 @@ rec {
    in
      if replaced == string then string else replaceStringsRec from to replaced;

+  toLower = replaceStrings upperChars lowerChars;
+
  squash = replaceStringsRec "\n\n\n" "\n\n";

  trim = string:
--- a/flake.lock
+++ b/flake.lock
@ -16,34 +16,34 @@
        "type": "github"
      }
    },
-    "lowdown-src": {
+    "libgit2": {
      "flake": false,
      "locked": {
-        "lastModified": 1633514407,
-        "narHash": "sha256-Dw32tiMjdK9t3ETl5fzGrutQTzh2rufgZV4A/BbxuD4=",
-        "owner": "kristapsdz",
-        "repo": "lowdown",
-        "rev": "d2c2b44ff6c27b936ec27358a2653caaef8f73b8",
+        "lastModified": 1697646580,
+        "narHash": "sha256-oX4Z3S9WtJlwvj0uH9HlYcWv+x1hqp8mhXl7HsLu2f0=",
+        "owner": "libgit2",
+        "repo": "libgit2",
+        "rev": "45fd9ed7ae1a9b74b957ef4f337bc3c8b3df01b5",
        "type": "github"
      },
      "original": {
-        "owner": "kristapsdz",
-        "repo": "lowdown",
+        "owner": "libgit2",
+        "repo": "libgit2",
        "type": "github"
      }
    },
    "nixpkgs": {
      "locked": {
-        "lastModified": 1698876495,
-        "narHash": "sha256-nsQo2/mkDUFeAjuu92p0dEqhRvHHiENhkKVIV1y0/Oo=",
+        "lastModified": 1705033721,
+        "narHash": "sha256-K5eJHmL1/kev6WuqyqqbS1cdNnSidIZ3jeqJ7GbrYnQ=",
        "owner": "NixOS",
        "repo": "nixpkgs",
-        "rev": "9eb24edd6a0027fed010ccfe300a9734d029983c",
+        "rev": "a1982c92d8980a0114372973cbdfe0a307f1bdea",
        "type": "github"
      },
      "original": {
        "owner": "NixOS",
-        "ref": "release-23.05",
+        "ref": "nixos-23.05-small",
        "repo": "nixpkgs",
        "type": "github"
      }
@ -67,7 +67,7 @@
    "root": {
      "inputs": {
        "flake-compat": "flake-compat",
-        "lowdown-src": "lowdown-src",
+        "libgit2": "libgit2",
        "nixpkgs": "nixpkgs",
        "nixpkgs-regression": "nixpkgs-regression"
      }
--- a/flake.nix
+++ b/flake.nix
@ -1,20 +1,29 @@
 {
  description = "The purely functional package manager";

-  # FIXME go back to nixos-23.05-small once
-  # https://github.com/NixOS/nixpkgs/pull/264875 is included.
-  inputs.nixpkgs.url = "github:NixOS/nixpkgs/release-23.05";
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-23.05-small";
  inputs.nixpkgs-regression.url = "github:NixOS/nixpkgs/215d4d0fd80ca5163643b03a33fde804a29cc1e2";
-  inputs.lowdown-src = { url = "github:kristapsdz/lowdown"; flake = false; };
  inputs.flake-compat = { url = "github:edolstra/flake-compat"; flake = false; };
+  inputs.libgit2 = { url = "github:libgit2/libgit2"; flake = false; };

-  outputs = { self, nixpkgs, nixpkgs-regression, lowdown-src, flake-compat }:
+  outputs = { self, nixpkgs, nixpkgs-regression, libgit2, ... }:

    let
      inherit (nixpkgs) lib;

+      # Experimental fileset library: https://github.com/NixOS/nixpkgs/pull/222981
+      # Not an "idiomatic" flake input because:
+      #  - Propagation to dependent locks: https://github.com/NixOS/nix/issues/7730
+      #  - Subflake would download redundant and huge parent flake
+      #  - No git tree hash support: https://github.com/NixOS/nix/issues/6044
+      inherit (import (builtins.fetchTarball { url = "https://github.com/NixOS/nix/archive/1bdcd7fc8a6a40b2e805bad759b36e64e911036b.tar.gz"; sha256 = "sha256:14ljlpdsp4x7h1fkhbmc4bd3vsqnx8zdql4h3037wh09ad6a0893"; }))
+        fileset;
+
      officialRelease = false;

+      # Set to true to build the release notes for the next release.
+      buildUnreleasedNotes = false;
+
      version = lib.fileContents ./.version + versionSuffix;
      versionSuffix =
        if officialRelease
@ -28,11 +37,26 @@
      systems = linuxSystems ++ darwinSystems;

      crossSystems = [
-        "armv6l-linux" "armv7l-linux"
-        "x86_64-freebsd13" "x86_64-netbsd"
+        "armv6l-unknown-linux-gnueabihf"
+        "armv7l-unknown-linux-gnueabihf"
+        "x86_64-unknown-freebsd13"
+        "x86_64-unknown-netbsd"
      ];

-      stdenvs = [ "gccStdenv" "clangStdenv" "clang11Stdenv" "stdenv" "libcxxStdenv" "ccacheStdenv" ];
+      # Nix doesn't yet build on this platform, so we put it in a
+      # separate list. We just use this for `devShells` and
+      # `nixpkgsFor`, which this depends on.
+      shellCrossSystems = crossSystems ++ [
+        "x86_64-w64-mingw32"
+      ];
+
+      stdenvs = [
+        "ccacheStdenv"
+        "clangStdenv"
+        "gccStdenv"
+        "libcxxStdenv"
+        "stdenv"
+      ];

      forAllSystems = lib.genAttrs systems;

@ -47,57 +71,6 @@
            })
            stdenvs);

-      # Experimental fileset library: https://github.com/NixOS/nixpkgs/pull/222981
-      # Not an "idiomatic" flake input because:
-      #  - Propagation to dependent locks: https://github.com/NixOS/nix/issues/7730
-      #  - Subflake would download redundant and huge parent flake
-      #  - No git tree hash support: https://github.com/NixOS/nix/issues/6044
-      inherit (import (builtins.fetchTarball { url = "https://github.com/NixOS/nix/archive/1bdcd7fc8a6a40b2e805bad759b36e64e911036b.tar.gz"; sha256 = "sha256:14ljlpdsp4x7h1fkhbmc4bd3vsqnx8zdql4h3037wh09ad6a0893"; }))
-        fileset;
-
-      baseFiles =
-        # .gitignore has already been processed, so any changes in it are irrelevant
-        # at this point. It is not represented verbatim for test purposes because
-        # that would interfere with repo semantics.
-        fileset.fileFilter (f: f.name != ".gitignore") ./.;
-
-      configureFiles = fileset.unions [
-        ./.version
-        ./configure.ac
-        ./m4
-        # TODO: do we really need README.md? It doesn't seem used in the build.
-        ./README.md
-      ];
-
-      topLevelBuildFiles = fileset.unions [
-        ./local.mk
-        ./Makefile
-        ./Makefile.config.in
-        ./mk
-      ];
-
-      functionalTestFiles = fileset.unions [
-        ./tests/functional
-        (fileset.fileFilter (f: lib.strings.hasPrefix "nix-profile" f.name) ./scripts)
-      ];
-
-      nixSrc = fileset.toSource {
-        root = ./.;
-        fileset = fileset.intersect baseFiles (fileset.unions [
-          configureFiles
-          topLevelBuildFiles
-          ./boehmgc-coroutine-sp-fallback.diff
-          ./doc
-          ./misc
-          ./precompiled-headers.h
-          ./src
-          ./unit-test-data
-          ./COPYING
-          ./scripts/local.mk
-          functionalTestFiles
-        ]);
-      };
-
      # Memoize nixpkgs for different platforms for efficiency.
      nixpkgsFor = forAllSystems
        (system: let
@ -106,8 +79,8 @@
              inherit system;
            };
            crossSystem = if crossSystem == null then null else {
-              system = crossSystem;
-            } // lib.optionalAttrs (crossSystem == "x86_64-freebsd13") {
+              config = crossSystem;
+            } // lib.optionalAttrs (crossSystem == "x86_64-unknown-freebsd13") {
              useLLVM = true;
            };
            overlays = [
@ -119,17 +92,43 @@
        in {
          inherit stdenvs native;
          static = native.pkgsStatic;
-          cross = forAllCrossSystems (crossSystem: make-pkgs crossSystem "stdenv");
+          cross = lib.genAttrs shellCrossSystems (crossSystem: make-pkgs crossSystem "stdenv");
        });

-      commonDeps =
-        { pkgs
-        , isStatic ? pkgs.stdenv.hostPlatform.isStatic
-        }:
-        with pkgs; rec {
-        # Use "busybox-sandbox-shell" if present,
-        # if not (legacy) fallback and hope it's sufficient.
-        sh = pkgs.busybox-sandbox-shell or (busybox.override {
+      installScriptFor = tarballs:
+        nixpkgsFor.x86_64-linux.native.callPackage ./scripts/installer.nix {
+          inherit tarballs;
+        };
+
+      testNixVersions = pkgs: client: daemon:
+        pkgs.callPackage ./package.nix {
+          pname =
+            "nix-tests"
+            + lib.optionalString
+              (lib.versionAtLeast daemon.version "2.4pre20211005" &&
+               lib.versionAtLeast client.version "2.4pre20211005")
+              "-${client.version}-against-${daemon.version}";
+
+          inherit fileset;
+
+          test-client = client;
+          test-daemon = daemon;
+
+          doBuild = false;
+        };
+
+      binaryTarball = nix: pkgs: pkgs.callPackage ./scripts/binary-tarball.nix {
+        inherit nix;
+      };
+
+      overlayFor = getStdenv: final: prev:
+        let
+          stdenv = getStdenv final;
+        in
+        {
+          nixStable = prev.nix;
+
+          default-busybox-sandbox-shell = final.busybox.override {
            useMusl = true;
            enableStatic = true;
            enableMinimal = true;
@ -151,362 +150,57 @@
              CONFIG_ASH_PRINTF y
              CONFIG_ASH_TEST y
            '';
+          };
+
+          libgit2-nix = final.libgit2.overrideAttrs (attrs: {
+            src = libgit2;
+            version = libgit2.lastModifiedDate;
+            cmakeFlags = attrs.cmakeFlags or []
+              ++ [ "-DUSE_SSH=exec" ];
          });

-        configureFlags =
-          lib.optionals stdenv.isLinux [
-            "--with-boost=${boost}/lib"
-            "--with-sandbox-shell=${sh}/bin/busybox"
-          ]
-          ++ lib.optionals (stdenv.isLinux && !(isStatic && stdenv.system == "aarch64-linux")) [
-            "LDFLAGS=-fuse-ld=gold"
-          ];
-
-        testConfigureFlags = [
-          "RAPIDCHECK_HEADERS=${lib.getDev rapidcheck}/extras/gtest/include"
-        ] ++ lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
-          "--enable-install-unit-tests"
-          "--with-check-bin-dir=${builtins.placeholder "check"}/bin"
-          "--with-check-lib-dir=${builtins.placeholder "check"}/lib"
-        ];
-
-        internalApiDocsConfigureFlags = [
-          "--enable-internal-api-docs"
-        ];
-
-        nativeBuildDeps =
-          [
-            buildPackages.bison
-            buildPackages.flex
-            (lib.getBin buildPackages.lowdown-nix)
-            buildPackages.mdbook
-            buildPackages.mdbook-linkcheck
-            buildPackages.autoconf-archive
-            buildPackages.autoreconfHook
-            buildPackages.pkg-config
-
-            # Tests
-            buildPackages.git
-            buildPackages.mercurial # FIXME: remove? only needed for tests
-            buildPackages.jq # Also for custom mdBook preprocessor.
-            buildPackages.openssh # only needed for tests (ssh-keygen)
-          ]
-          ++ lib.optionals stdenv.hostPlatform.isLinux [(buildPackages.util-linuxMinimal or buildPackages.utillinuxMinimal)];
-
-        buildDeps =
-          [ curl
-            bzip2 xz brotli editline
-            openssl sqlite
-            libarchive
-            boost
-            lowdown-nix
-            libsodium
-          ]
-          ++ lib.optionals stdenv.isLinux [libseccomp]
-          ++ lib.optional stdenv.hostPlatform.isx86_64 libcpuid;
-
-        checkDeps = [
-          gtest
-          rapidcheck
-        ];
-
-        internalApiDocsDeps = [
-          buildPackages.doxygen
-        ];
-
-        awsDeps = lib.optional (stdenv.isLinux || stdenv.isDarwin)
-          (aws-sdk-cpp.override {
-            apis = ["s3" "transfer"];
-            customMemoryManagement = false;
-          });
-
-        propagatedDeps =
-          [ ((boehmgc.override {
+          boehmgc-nix = (final.boehmgc.override {
            enableLargeConfig = true;
          }).overrideAttrs(o: {
            patches = (o.patches or []) ++ [
-                ./boehmgc-coroutine-sp-fallback.diff
+              ./dep-patches/boehmgc-coroutine-sp-fallback.diff
+
+              # https://github.com/ivmai/bdwgc/pull/586
+              ./dep-patches/boehmgc-traceable_allocator-public.diff
            ];
-            })
-            )
-            nlohmann_json
-          ];
-      };
-
-      installScriptFor = systems:
-        with nixpkgsFor.x86_64-linux.native;
-        runCommand "installer-script"
-          { buildInputs = [ nix ];
-          }
-          ''
-            mkdir -p $out/nix-support
-
-            # Converts /nix/store/50p3qk8k...-nix-2.4pre20201102_550e11f/bin/nix to 50p3qk8k.../bin/nix.
-            tarballPath() {
-              # Remove the store prefix
-              local path=''${1#${builtins.storeDir}/}
-              # Get the path relative to the derivation root
-              local rest=''${path#*/}
-              # Get the derivation hash
-              local drvHash=''${path%%-*}
-              echo "$drvHash/$rest"
-            }
-
-            substitute ${./scripts/install.in} $out/install \
-              ${pkgs.lib.concatMapStrings
-                (system: let
-                    tarball = if builtins.elem system crossSystems then self.hydraJobs.binaryTarballCross.x86_64-linux.${system} else self.hydraJobs.binaryTarball.${system};
-                  in '' \
-                  --replace '@tarballHash_${system}@' $(nix --experimental-features nix-command hash-file --base16 --type sha256 ${tarball}/*.tar.xz) \
-                  --replace '@tarballPath_${system}@' $(tarballPath ${tarball}/*.tar.xz) \
-                  ''
-                )
-                systems
-              } --replace '@nixVersion@' ${version}
-
-            echo "file installer $out/install" >> $out/nix-support/hydra-build-products
-          '';
-
-      testNixVersions = pkgs: client: daemon: with commonDeps { inherit pkgs; }; with pkgs.lib; pkgs.stdenv.mkDerivation {
-        NIX_DAEMON_PACKAGE = daemon;
-        NIX_CLIENT_PACKAGE = client;
-        name =
-          "nix-tests"
-          + optionalString
-            (versionAtLeast daemon.version "2.4pre20211005" &&
-             versionAtLeast client.version "2.4pre20211005")
-            "-${client.version}-against-${daemon.version}";
-        inherit version;
-
-        src = fileset.toSource {
-          root = ./.;
-          fileset = fileset.intersect baseFiles (fileset.unions [
-            configureFiles
-            topLevelBuildFiles
-            functionalTestFiles
-          ]);
-        };
-
-        VERSION_SUFFIX = versionSuffix;
-
-        nativeBuildInputs = nativeBuildDeps;
-        buildInputs = buildDeps ++ awsDeps ++ checkDeps;
-        propagatedBuildInputs = propagatedDeps;
-
-        enableParallelBuilding = true;
-
-        configureFlags =
-          testConfigureFlags # otherwise configure fails
-          ++ [ "--disable-build" ];
-        dontBuild = true;
-        doInstallCheck = true;
-
-        installPhase = ''
-          mkdir -p $out
-        '';
-
-        installCheckPhase = ''
-          mkdir -p src/nix-channel
-          make installcheck -j$NIX_BUILD_CORES -l$NIX_BUILD_CORES
-        '';
-      };
-
-      binaryTarball = nix: pkgs:
-        let
-          inherit (pkgs) buildPackages;
-          inherit (pkgs) cacert;
-          installerClosureInfo = buildPackages.closureInfo { rootPaths = [ nix cacert ]; };
-        in
-
-        buildPackages.runCommand "nix-binary-tarball-${version}"
-          { #nativeBuildInputs = lib.optional (system != "aarch64-linux") shellcheck;
-            meta.description = "Distribution-independent Nix bootstrap binaries for ${pkgs.system}";
-          }
-          ''
-            cp ${installerClosureInfo}/registration $TMPDIR/reginfo
-            cp ${./scripts/create-darwin-volume.sh} $TMPDIR/create-darwin-volume.sh
-            substitute ${./scripts/install-nix-from-closure.sh} $TMPDIR/install \
-              --subst-var-by nix ${nix} \
-              --subst-var-by cacert ${cacert}
-
-            substitute ${./scripts/install-darwin-multi-user.sh} $TMPDIR/install-darwin-multi-user.sh \
-              --subst-var-by nix ${nix} \
-              --subst-var-by cacert ${cacert}
-            substitute ${./scripts/install-systemd-multi-user.sh} $TMPDIR/install-systemd-multi-user.sh \
-              --subst-var-by nix ${nix} \
-              --subst-var-by cacert ${cacert}
-            substitute ${./scripts/install-multi-user.sh} $TMPDIR/install-multi-user \
-              --subst-var-by nix ${nix} \
-              --subst-var-by cacert ${cacert}
-
-            if type -p shellcheck; then
-              # SC1090: Don't worry about not being able to find
-              #         $nix/etc/profile.d/nix.sh
-              shellcheck --exclude SC1090 $TMPDIR/install
-              shellcheck $TMPDIR/create-darwin-volume.sh
-              shellcheck $TMPDIR/install-darwin-multi-user.sh
-              shellcheck $TMPDIR/install-systemd-multi-user.sh
-
-              # SC1091: Don't panic about not being able to source
-              #         /etc/profile
-              # SC2002: Ignore "useless cat" "error", when loading
-              #         .reginfo, as the cat is a much cleaner
-              #         implementation, even though it is "useless"
-              # SC2116: Allow ROOT_HOME=$(echo ~root) for resolving
-              #         root's home directory
-              shellcheck --external-sources \
-                --exclude SC1091,SC2002,SC2116 $TMPDIR/install-multi-user
-            fi
-
-            chmod +x $TMPDIR/install
-            chmod +x $TMPDIR/create-darwin-volume.sh
-            chmod +x $TMPDIR/install-darwin-multi-user.sh
-            chmod +x $TMPDIR/install-systemd-multi-user.sh
-            chmod +x $TMPDIR/install-multi-user
-            dir=nix-${version}-${pkgs.system}
-            fn=$out/$dir.tar.xz
-            mkdir -p $out/nix-support
-            echo "file binary-dist $fn" >> $out/nix-support/hydra-build-products
-            tar cvfJ $fn \
-              --owner=0 --group=0 --mode=u+rw,uga+r \
-              --mtime='1970-01-01' \
-              --absolute-names \
-              --hard-dereference \
-              --transform "s,$TMPDIR/install,$dir/install," \
-              --transform "s,$TMPDIR/create-darwin-volume.sh,$dir/create-darwin-volume.sh," \
-              --transform "s,$TMPDIR/reginfo,$dir/.reginfo," \
-              --transform "s,$NIX_STORE,$dir/store,S" \
-              $TMPDIR/install \
-              $TMPDIR/create-darwin-volume.sh \
-              $TMPDIR/install-darwin-multi-user.sh \
-              $TMPDIR/install-systemd-multi-user.sh \
-              $TMPDIR/install-multi-user \
-              $TMPDIR/reginfo \
-              $(cat ${installerClosureInfo}/store-paths)
-          '';
-
-      overlayFor = getStdenv: final: prev:
-        let currentStdenv = getStdenv final; in
-        {
-          nixStable = prev.nix;
-
-          # Forward from the previous stage as we don’t want it to pick the lowdown override
-          nixUnstable = prev.nixUnstable;
-
-          nix =
-          with final;
-          with commonDeps {
-            inherit pkgs;
-            inherit (currentStdenv.hostPlatform) isStatic;
-          };
-          let
-            canRunInstalled = currentStdenv.buildPlatform.canExecute currentStdenv.hostPlatform;
-          in currentStdenv.mkDerivation (finalAttrs: {
-            name = "nix-${version}";
-            inherit version;
-
-            src = nixSrc;
-            VERSION_SUFFIX = versionSuffix;
-
-            outputs = [ "out" "dev" "doc" ]
-              ++ lib.optional (currentStdenv.hostPlatform != currentStdenv.buildPlatform) "check";
-
-            nativeBuildInputs = nativeBuildDeps;
-            buildInputs = buildDeps
-              # There have been issues building these dependencies
-              ++ lib.optionals (currentStdenv.hostPlatform == currentStdenv.buildPlatform) awsDeps
-              ++ lib.optionals finalAttrs.doCheck checkDeps;
-
-            propagatedBuildInputs = propagatedDeps;
-
-            disallowedReferences = [ boost ];
-
-            preConfigure = lib.optionalString (! currentStdenv.hostPlatform.isStatic)
-              ''
-                # Copy libboost_context so we don't get all of Boost in our closure.
-                # https://github.com/NixOS/nixpkgs/issues/45462
-                mkdir -p $out/lib
-                cp -pd ${boost}/lib/{libboost_context*,libboost_thread*,libboost_system*} $out/lib
-                rm -f $out/lib/*.a
-                ${lib.optionalString currentStdenv.hostPlatform.isLinux ''
-                  chmod u+w $out/lib/*.so.*
-                  patchelf --set-rpath $out/lib:${currentStdenv.cc.cc.lib}/lib $out/lib/libboost_thread.so.*
-                ''}
-                ${lib.optionalString currentStdenv.hostPlatform.isDarwin ''
-                  for LIB in $out/lib/*.dylib; do
-                    chmod u+w $LIB
-                    install_name_tool -id $LIB $LIB
-                    install_name_tool -delete_rpath ${boost}/lib/ $LIB || true
-                  done
-                  install_name_tool -change ${boost}/lib/libboost_system.dylib $out/lib/libboost_system.dylib $out/lib/libboost_thread.dylib
-                ''}
-              '';
-
-            configureFlags = configureFlags ++
-              [ "--sysconfdir=/etc" ] ++
-              lib.optional stdenv.hostPlatform.isStatic "--enable-embedded-sandbox-shell" ++
-              [ (lib.enableFeature finalAttrs.doCheck "tests") ] ++
-              lib.optionals finalAttrs.doCheck testConfigureFlags ++
-              lib.optional (!canRunInstalled) "--disable-doc-gen";
-
-            enableParallelBuilding = true;
-
-            makeFlags = "profiledir=$(out)/etc/profile.d PRECOMPILE_HEADERS=1";
-
-            doCheck = true;
-
-            installFlags = "sysconfdir=$(out)/etc";
-
-            postInstall = ''
-              mkdir -p $doc/nix-support
-              echo "doc manual $doc/share/doc/nix/manual" >> $doc/nix-support/hydra-build-products
-              ${lib.optionalString currentStdenv.hostPlatform.isStatic ''
-              mkdir -p $out/nix-support
-              echo "file binary-dist $out/bin/nix" >> $out/nix-support/hydra-build-products
-              ''}
-              ${lib.optionalString currentStdenv.isDarwin ''
-              install_name_tool \
-                -change ${boost}/lib/libboost_context.dylib \
-                $out/lib/libboost_context.dylib \
-                $out/lib/libnixutil.dylib
-              ''}
-            '';
-
-            doInstallCheck = finalAttrs.doCheck;
-            installCheckFlags = "sysconfdir=$(out)/etc";
-            installCheckTarget = "installcheck"; # work around buggy detection in stdenv
-
-            separateDebugInfo = !currentStdenv.hostPlatform.isStatic;
-
-            strictDeps = true;
-
-            hardeningDisable = lib.optional stdenv.hostPlatform.isStatic "pie";
-
-            passthru.perl-bindings = final.callPackage ./perl {
-              inherit fileset;
-              stdenv = currentStdenv;
-            };
-
-            meta.platforms = lib.platforms.unix;
-            meta.mainProgram = "nix";
          });

-          lowdown-nix = with final; currentStdenv.mkDerivation rec {
-            name = "lowdown-0.9.0";
+          changelog-d-nix = final.buildPackages.callPackage ./misc/changelog-d.nix { };

-            src = lowdown-src;
+          nix =
+            let
+              officialRelease = false;
+              versionSuffix =
+                if officialRelease
+                then ""
+                else "pre${builtins.substring 0 8 (self.lastModifiedDate or self.lastModified or "19700101")}_${self.shortRev or "dirty"}";

-            outputs = [ "out" "bin" "dev" ];
-
-            nativeBuildInputs = [ buildPackages.which ];
-
-            configurePhase = ''
-                ${if (currentStdenv.isDarwin && currentStdenv.isAarch64) then "echo \"HAVE_SANDBOX_INIT=false\" > configure.local" else ""}
-                ./configure \
-                  PREFIX=${placeholder "dev"} \
-                  BINDIR=${placeholder "bin"}/bin
-            '';
+            in final.callPackage ./package.nix {
+              inherit
+                fileset
+                stdenv
+                versionSuffix
+                ;
+              officialRelease = false;
+              boehmgc = final.boehmgc-nix;
+              libgit2 = final.libgit2-nix;
+              busybox-sandbox-shell = final.busybox-sandbox-shell or final.default-busybox-sandbox-shell;
+              changelog-d = final.changelog-d-nix;
+            } // {
+              # this is a proper separate downstream package, but put
+              # here also for back compat reasons.
+              perl-bindings = final.nix-perl-bindings;
            };
+
+          nix-perl-bindings = final.callPackage ./perl {
+            inherit fileset stdenv;
+          };
+
        };

    in {
@ -519,19 +213,32 @@
        # Binary package for various platforms.
        build = forAllSystems (system: self.packages.${system}.nix);

+        shellInputs = forAllSystems (system: self.devShells.${system}.default.inputDerivation);
+
        buildStatic = lib.genAttrs linux64BitSystems (system: self.packages.${system}.nix-static);

        buildCross = forAllCrossSystems (crossSystem:
          lib.genAttrs ["x86_64-linux"] (system: self.packages.${system}."nix-${crossSystem}"));

-        buildNoGc = forAllSystems (system: self.packages.${system}.nix.overrideAttrs (a: { configureFlags = (a.configureFlags or []) ++ ["--enable-gc=no"];}));
+        buildNoGc = forAllSystems (system:
+          self.packages.${system}.nix.override { enableGC = false; }
+        );

        buildNoTests = forAllSystems (system:
-          self.packages.${system}.nix.overrideAttrs (a: {
-            doCheck =
-              assert ! a?dontCheck;
-              false;
-          })
+          self.packages.${system}.nix.override {
+            doCheck = false;
+            doInstallCheck = false;
+            installUnitTests = false;
+          }
+        );
+
+        # Toggles some settings for better coverage. Windows needs these
+        # library combinations, and Debian build Nix with GNU readline too.
+        buildReadlineNoMarkdown = forAllSystems (system:
+          self.packages.${system}.nix.override {
+            enableMarkdown = false;
+            readlineFlavor = "readline";
+          }
        );

        # Perl bindings for various platforms.
@ -552,66 +259,40 @@
        # to https://nixos.org/nix/install. It downloads the binary
        # tarball for the user's system and calls the second half of the
        # installation script.
-        installerScript = installScriptFor [ "x86_64-linux" "i686-linux" "aarch64-linux" "x86_64-darwin" "aarch64-darwin" "armv6l-linux" "armv7l-linux" ];
-        installerScriptForGHA = installScriptFor [ "x86_64-linux" "x86_64-darwin" "armv6l-linux" "armv7l-linux"];
+        installerScript = installScriptFor [
+          # Native
+          self.hydraJobs.binaryTarball."x86_64-linux"
+          self.hydraJobs.binaryTarball."i686-linux"
+          self.hydraJobs.binaryTarball."aarch64-linux"
+          self.hydraJobs.binaryTarball."x86_64-darwin"
+          self.hydraJobs.binaryTarball."aarch64-darwin"
+          # Cross
+          self.hydraJobs.binaryTarballCross."x86_64-linux"."armv6l-unknown-linux-gnueabihf"
+          self.hydraJobs.binaryTarballCross."x86_64-linux"."armv7l-unknown-linux-gnueabihf"
+        ];
+        installerScriptForGHA = installScriptFor [
+          # Native
+          self.hydraJobs.binaryTarball."x86_64-linux"
+          self.hydraJobs.binaryTarball."x86_64-darwin"
+          # Cross
+          self.hydraJobs.binaryTarballCross."x86_64-linux"."armv6l-unknown-linux-gnueabihf"
+          self.hydraJobs.binaryTarballCross."x86_64-linux"."armv7l-unknown-linux-gnueabihf"
+        ];

        # docker image with Nix inside
        dockerImage = lib.genAttrs linux64BitSystems (system: self.packages.${system}.dockerImage);

        # Line coverage analysis.
-        coverage =
-          with nixpkgsFor.x86_64-linux.native;
-          with commonDeps { inherit pkgs; };
-
-          releaseTools.coverageAnalysis {
-            name = "nix-coverage-${version}";
-
-            src = nixSrc;
-
-            configureFlags = testConfigureFlags;
-
-            enableParallelBuilding = true;
-
-            nativeBuildInputs = nativeBuildDeps;
-            buildInputs = buildDeps ++ propagatedDeps ++ awsDeps ++ checkDeps;
-
-            dontInstall = false;
-
-            doInstallCheck = true;
-            installCheckTarget = "installcheck"; # work around buggy detection in stdenv
-
-            lcovFilter = [ "*/boost/*" "*-tab.*" ];
-
-            hardeningDisable = ["fortify"];
-
-            NIX_CFLAGS_COMPILE = "-DCOVERAGE=1";
+        coverage = nixpkgsFor.x86_64-linux.native.nix.override {
+          pname = "nix-coverage";
+          withCoverageChecks = true;
        };

        # API docs for Nix's unstable internal C++ interfaces.
-        internal-api-docs =
-          with nixpkgsFor.x86_64-linux.native;
-          with commonDeps { inherit pkgs; };
-
-          stdenv.mkDerivation {
-            pname = "nix-internal-api-docs";
-            inherit version;
-
-            src = nixSrc;
-
-            configureFlags = testConfigureFlags ++ internalApiDocsConfigureFlags;
-
-            nativeBuildInputs = nativeBuildDeps;
-            buildInputs = buildDeps ++ propagatedDeps
-              ++ awsDeps ++ checkDeps ++ internalApiDocsDeps;
-
-            dontBuild = true;
-
-            installTargets = [ "internal-api-html" ];
-
-            postInstall = ''
-              mkdir -p $out/nix-support
-              echo "doc internal-api-docs $out/share/doc/nix/internal-api/html" >> $out/nix-support/hydra-build-products
-            '';
+        internal-api-docs = nixpkgsFor.x86_64-linux.native.callPackage ./package.nix {
+          inherit fileset;
+          doBuild = false;
+          enableInternalAPIDocs = true;
        };

        # System tests.
@ -620,7 +301,9 @@
          # Make sure that nix-env still produces the exact same result
          # on a particular version of Nixpkgs.
          evalNixpkgs =
-            with nixpkgsFor.x86_64-linux.native;
+            let
+              inherit (nixpkgsFor.x86_64-linux.native) runCommand nix;
+            in
            runCommand "eval-nixos" { buildInputs = [ nix ]; }
              ''
                type -p nix-env
@ -670,6 +353,11 @@
        perlBindings = self.hydraJobs.perlBindings.${system};
        installTests = self.hydraJobs.installTests.${system};
        nixpkgsLibTests = self.hydraJobs.tests.nixpkgsLibTests.${system};
+        rl-next =
+          let pkgs = nixpkgsFor.${system}.native;
+          in pkgs.buildPackages.runCommand "test-rl-next-release-notes" { } ''
+          LANG=C.UTF-8 ${pkgs.changelog-d-nix}/bin/changelog-d ${./doc/manual/rl-next} >$out
+        '';
      } // (lib.optionalAttrs (builtins.elem system linux64BitSystems)) {
        dockerImage = self.hydraJobs.dockerImage.${system};
      });
@ -707,37 +395,9 @@
          stdenvs)));

      devShells = let
-        makeShell = pkgs: stdenv:
-          let
-            canRunInstalled = stdenv.buildPlatform.canExecute stdenv.hostPlatform;
-          in
-          with commonDeps { inherit pkgs; };
-          stdenv.mkDerivation {
-            name = "nix";
-
-            outputs = [ "out" "dev" "doc" ]
-              ++ lib.optional (stdenv.hostPlatform != stdenv.buildPlatform) "check";
-
-            nativeBuildInputs = nativeBuildDeps
-              ++ lib.optional stdenv.cc.isClang pkgs.buildPackages.bear
-              ++ lib.optional
-                (stdenv.cc.isClang && stdenv.hostPlatform == stdenv.buildPlatform)
-                pkgs.buildPackages.clang-tools
-              ;
-
-            buildInputs = buildDeps ++ propagatedDeps
-              ++ awsDeps ++ checkDeps ++ internalApiDocsDeps;
-
-            configureFlags = configureFlags
-              ++ testConfigureFlags ++ internalApiDocsConfigureFlags
-              ++ lib.optional (!canRunInstalled) "--disable-doc-gen";
-
-            enableParallelBuilding = true;
-
+        makeShell = pkgs: stdenv: (pkgs.nix.override { inherit stdenv; forDevShell = true; }).overrideAttrs (attrs: {
          installFlags = "sysconfdir=$(out)/etc";
-
-            shellHook =
-              ''
+          shellHook = ''
            PATH=$prefix/bin:$PATH
            unset PYTHONPATH
            export MANPATH=$out/share/man:$MANPATH
@ -745,7 +405,10 @@
            # Make bash completion work.
            XDG_DATA_DIRS+=:$out/share
          '';
-          };
+          nativeBuildInputs = attrs.nativeBuildInputs or []
+            ++ lib.optional stdenv.cc.isClang pkgs.buildPackages.bear
+            ++ lib.optional (stdenv.cc.isClang && stdenv.hostPlatform == stdenv.buildPlatform) pkgs.buildPackages.clang-tools;
+        });
        in
        forAllSystems (system:
          let
@ -756,7 +419,7 @@
          in
            (makeShells "native" nixpkgsFor.${system}.native) //
            (makeShells "static" nixpkgsFor.${system}.static) //
-            (forAllCrossSystems (crossSystem: let pkgs = nixpkgsFor.${system}.cross.${crossSystem}; in makeShell pkgs pkgs.stdenv)) //
+            (lib.genAttrs shellCrossSystems (crossSystem: let pkgs = nixpkgsFor.${system}.cross.${crossSystem}; in makeShell pkgs pkgs.stdenv)) //
            {
              default = self.devShells.${system}.native-stdenvPackages;
            }
--- a/maintainers/release-notes
+++ b/maintainers/release-notes
@ -0,0 +1,179 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash ../shell.nix -I nixpkgs=channel:nixos-unstable-small
+#                                   ^^^^^^^
+#                Only used for bash. shell.nix goes to the flake.
+
+# --- CONFIGURATION ---
+
+# This does double duty for
+# - including rl-next
+# - marking where to insert new links (right after)
+SUMMARY_MARKER_LINE='{{#include ./SUMMARY-rl-next.md}}'
+
+# --- LIB ---
+
+log() {
+  echo 1>&2 "release-notes:" "$@"
+}
+logcmd() {
+  local cmd="$1"
+  shift
+  logcmd2 "$cmd" "${*@Q}" "$cmd" "$@"
+}
+logcmd2() {
+  local fakecmd="$1"
+  local fakeargs="$2"
+  shift
+  shift
+  printf 1>&2 "release-notes: \033[34;1m$fakecmd\033[0m "
+  echo "$fakeargs" 1>&2
+  "$@"
+}
+die() {
+  # ANSI red
+  printf 1>&2 "release-notes: \033[31;1merror:\033[0m"
+  echo 1>&2 "" "$@"
+  exit 1
+}
+confirm() {
+  local answer
+  echo 1>&2 "$@" "[y/n]"
+  read -r answer
+  case "$answer" in
+    y|Y|yes|Yes|YES)
+      return 0
+      ;;
+    n|N|no|No|NO)
+      return 1
+      ;;
+    *)
+      echo 1>&2 "please answer y or n"
+      confirm "$@"
+      ;;
+  esac
+}
+report_done() {
+  logcmd2 "git" "show" git -c pager.show=false show
+  printf 1>&2 "release-notes: \033[32;1mdone\033[0m\n"
+}
+
+# --- PARSE ARGS ---
+
+if [[ $# -gt 0 ]]; then
+  die "Release notes takes no arguments, but make sure to set VERSION."
+fi
+
+# --- CHECKS ---
+
+if [[ ! -e flake.nix ]] || [[ ! -e .git ]]; then
+  die "must run in repo root"
+  exit 1
+fi
+
+# repo must be clean
+if ! git diff --quiet; then
+  die "repo is dirty, please commit or stash changes"
+fi
+
+if ! git diff --quiet --cached; then
+  die "repo has staged changes, please commit or stash them"
+fi
+
+if ! grep "$SUMMARY_MARKER_LINE" doc/manual/src/SUMMARY.md.in >/dev/null; then
+  # would have been nice to catch this early, but won't be worth the extra infra
+  die "SUMMARY.md.in is missing the marker line '$SUMMARY_MARKER_LINE', which would be used for inserting a new release notes page. Please fix the script."
+fi
+
+if [[ ! -n "${VERSION:-}" ]]; then
+  die "please set the VERSION environment variable before invoking this script"
+  exit 1
+fi
+
+# version_major_minor:      MAJOR.MINOR
+# version_full:             MAJOR.MINOR.PATCH
+# IS_PATCH:                 true if this is a patch release; append instead of create
+if grep -E '^[0-9]+\.[0-9]+$' <<< "$VERSION" >/dev/null; then
+  log 'is minor'
+  IS_PATCH=false
+  version_full="$VERSION.0"
+  version_major_minor="$VERSION"
+elif grep -E '^[0-9]+\.[0-9]+\.0$' <<< "$VERSION" >/dev/null; then
+  log 'is minor (.0)'
+  IS_PATCH=false
+  version_full="$VERSION"
+  version_major_minor="$(echo "$VERSION" | sed -e 's/\.0$//')"
+elif grep -E '^[0-9]+\.[0-9]+\.[0-9]+$' <<< "$VERSION" >/dev/null; then
+  log 'is patch'
+  IS_PATCH=true
+  version_full="$VERSION"
+  version_major_minor="$(echo "$VERSION" | sed -e 's/\.[0-9]*$//')"
+else
+  die "VERSION must be MAJOR.MINOR[.PATCH], where each is a number, e.g. 2.20 or 2.20.1 (VERSION was set to $VERSION)"
+fi
+
+unset VERSION
+
+log "version_major_minor=$version_major_minor"
+log "version_full=$version_full"
+log "IS_PATCH=$IS_PATCH"
+
+basename=rl-${version_major_minor}.md
+file=doc/manual/src/release-notes/$basename
+
+if ! $IS_PATCH; then
+  if [[ -e $file ]]; then
+    die "release notes file $file already exists. If you'd like to make a minor release, pass a patch version, e.g. 2.20.1"
+  fi
+fi
+
+# --- DEFAULTS ---
+
+if [[ ! -n "${DATE:-}" ]]; then
+  DATE="$(date +%Y-%m-%d)"
+  log "DATE not set, using $DATE"
+fi
+
+case "$DATE" in
+  [0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9])
+    ;;
+  *)
+    die "DATE must be YYYY-MM-DD, e.g. 2021-12-31 (DATE was set to $DATE)"
+    ;;
+esac
+
+# --- DO THE WORK ---
+
+# menu
+title="Release $version_major_minor ($DATE)"
+# section on page
+section_title="Release $version_full ($DATE)"
+
+(
+  # TODO add minor number, and append?
+  echo "# $section_title"
+  echo
+  changelog-d doc/manual/rl-next | sed -e 's/ *$//'
+) | tee -a $file
+
+log "Wrote $file"
+
+if ! $IS_PATCH; then
+  NEW_SUMMARY_LINE="  - [$title](release-notes/$basename)"
+
+  # find the marker line, insert new link after it
+  escaped_marker="$(echo "$SUMMARY_MARKER_LINE" | sed -e 's/\//\\\//g' -e 's/ /\\ /g')"
+  escaped_line="$(echo "$NEW_SUMMARY_LINE" | sed -e 's/\//\\\//g' -e 's/ /\\ /g')"
+  logcmd sed -i -e "/$escaped_marker/a $escaped_line" doc/manual/src/SUMMARY.md.in
+fi
+
+for f in doc/manual/rl-next/*.md; do
+  if [[ config != "$(basename $f)" ]]; then
+    logcmd git rm $f
+  fi
+done
+
+logcmd git add $file doc/manual/src/SUMMARY.md.in
+logcmd git status
+logcmd git commit -m "release notes: $version_full"
+
+report_done
--- a/maintainers/release-process.md
+++ b/maintainers/release-process.md
@ -24,34 +24,23 @@ release:
 * In a checkout of the Nix repo, make sure you're on `master` and run
  `git pull`.

-* Move the contents of `doc/manual/src/release-notes/rl-next.md`
-  (except the first line) to
-  `doc/manual/src/release-notes/rl-$VERSION.md` (where `$VERSION` is
-  the contents of `.version` *without* the patch level, e.g. `2.12`
-  rather than `2.12.0`).
-
-* Add a header to `doc/manual/src/release-notes/rl-$VERSION.md` like
-
-  ```
-  # Release 2.12 (2022-12-06)
-  ```
-
-* Proof-read / edit / rearrange the release notes. Breaking changes
-  and highlights should go to the top.
-
-* Add a link to the release notes to `doc/manual/src/SUMMARY.md.in`
-  (*not* `SUMMARY.md`), e.g.
-
-  ```
-  - [Release 2.12 (2022-12-06)](release-notes/rl-2.12.md)
-  ```
-
-* Run
+* Compile the release notes by running

  ```console
  $ git checkout -b release-notes
-  $ git add doc/manual/src/release-notes/rl-$VERSION.md
-  $ git commit -a -m 'Release notes'
+  $ VERSION=X.YY ./maintainers/release-notes
+  ```
+
+  where `X.YY` is *without* the patch level, e.g. `2.12` rather than ~~`2.12.0`~~.
+
+  A commit is created.
+
+* Proof-read / edit / rearrange the release notes if needed. Breaking changes
+  and highlights should go to the top.
+
+* Push.
+
+  ```console
  $ git push --set-upstream $REMOTE release-notes
  ```

@ -67,15 +56,17 @@ release:
  $ git checkout -b $VERSION-maintenance
  ```

-* Mark the release as stable:
+* Mark the release as official:

  ```console
-  $ git cherry-pick f673551e71942a52b6d7ae66af8b67140904a76a
+  $ sed -e 's/officialRelease = false;/officialRelease = true;/' -i flake.nix
  ```

  This removes the link to `rl-next.md` from the manual and sets
  `officialRelease = true` in `flake.nix`.

+* Commit
+
 * Push the release branch:

  ```console
@ -159,6 +150,30 @@ release:

 ## Creating a point release

+* Checkout.
+
+  ```console
+  $ git checkout XX.YY-maintenance
+  ```
+
+* Determine the next patch version.
+
+  ```console
+  $ export VERSION=XX.YY.ZZ
+  ```
+
+* Update release notes.
+
+  ```console
+  $ ./maintainers/release-notes
+  ```
+
+* Push.
+
+  ```console
+  $ git push
+  ```
+
 * Wait for the desired evaluation of the maintenance jobset to finish
  building.

--- a/maintainers/upload-release.pl
+++ b/maintainers/upload-release.pl
@ -154,8 +154,8 @@ downloadFile("binaryTarball.x86_64-linux", "1");
 downloadFile("binaryTarball.aarch64-linux", "1");
 downloadFile("binaryTarball.x86_64-darwin", "1");
 downloadFile("binaryTarball.aarch64-darwin", "1");
-downloadFile("binaryTarballCross.x86_64-linux.armv6l-linux", "1");
-downloadFile("binaryTarballCross.x86_64-linux.armv7l-linux", "1");
+downloadFile("binaryTarballCross.x86_64-linux.armv6l-unknown-linux-gnueabihf", "1");
+downloadFile("binaryTarballCross.x86_64-linux.armv7l-unknown-linux-gnueabihf", "1");
 downloadFile("installerScript", "1");

 # Upload docker images to dockerhub.
--- a/misc/changelog-d.cabal.nix
+++ b/misc/changelog-d.cabal.nix
@ -0,0 +1,31 @@
+{ mkDerivation, aeson, base, bytestring, cabal-install-parsers
+, Cabal-syntax, containers, directory, filepath, frontmatter
+, generic-lens-lite, lib, mtl, optparse-applicative, parsec, pretty
+, regex-applicative, text, pkgs
+}:
+let rev = "f30f6969e9cd8b56242309639d58acea21c99d06";
+in
+mkDerivation {
+  pname = "changelog-d";
+  version = "0.1";
+  src = pkgs.fetchurl {
+    name = "changelog-d-${rev}.tar.gz";
+    url = "https://codeberg.org/roberth/changelog-d/archive/${rev}.tar.gz";
+    hash = "sha256-8a2+i5u7YoszAgd5OIEW0eYUcP8yfhtoOIhLJkylYJ4=";
+  } // { inherit rev; };
+  isLibrary = false;
+  isExecutable = true;
+  libraryHaskellDepends = [
+    aeson base bytestring cabal-install-parsers Cabal-syntax containers
+    directory filepath frontmatter generic-lens-lite mtl parsec pretty
+    regex-applicative text
+  ];
+  executableHaskellDepends = [
+    base bytestring Cabal-syntax directory filepath
+    optparse-applicative
+  ];
+  doHaddock = false;
+  description = "Concatenate changelog entries into a single one";
+  license = lib.licenses.gpl3Plus;
+  mainProgram = "changelog-d";
+}
--- a/misc/changelog-d.nix
+++ b/misc/changelog-d.nix
@ -0,0 +1,31 @@
+# Taken temporarily from <nixpkgs/pkgs/by-name/ch/changelog-d/package.nix>
+{
+  callPackage,
+  lib,
+  haskell,
+  haskellPackages,
+}:
+
+let
+  hsPkg = haskellPackages.callPackage ./changelog-d.cabal.nix { };
+
+  addCompletions = haskellPackages.generateOptparseApplicativeCompletions ["changelog-d"];
+
+  haskellModifications =
+    lib.flip lib.pipe [
+      addCompletions
+      haskell.lib.justStaticExecutables
+    ];
+
+  mkDerivationOverrides = finalAttrs: oldAttrs: {
+
+    version = oldAttrs.version + "-git-${lib.strings.substring 0 7 oldAttrs.src.rev}";
+
+    meta = oldAttrs.meta // {
+      homepage = "https://codeberg.org/roberth/changelog-d";
+      maintainers = [ lib.maintainers.roberth ];
+    };
+
+  };
+in
+  (haskellModifications hsPkg).overrideAttrs mkDerivationOverrides
--- a/mk/build-dir.mk
+++ b/mk/build-dir.mk
@ -0,0 +1,10 @@
+# Initialise support for build directories.
+builddir ?=
+
+ifdef builddir
+  buildprefix = $(builddir)/
+  buildprefixrel = $(builddir)
+else
+  buildprefix =
+  buildprefixrel = .
+endif
--- a/mk/common-test.sh
+++ b/mk/common-test.sh
@ -1,7 +1,7 @@
 # Remove overall test dir (at most one of the two should match) and
 # remove file extension.
 test_name=$(echo -n "$test" | sed \
-    -e "s|^unit-test-data/||" \
+    -e "s|^tests/unit/[^/]*/data/||" \
    -e "s|^tests/functional/||" \
    -e "s|\.sh$||" \
    )
--- a/mk/disable-tests.mk
+++ b/mk/disable-tests.mk
@ -1,12 +0,0 @@
-# This file is only active for `./configure --disable-tests`.
-# Running `make check` or `make installcheck` would indicate a mistake in the
-# caller.
-
-installcheck:
-	@echo "Tests are disabled. Configure without '--disable-tests', or avoid calling 'make installcheck'."
-	@exit 1
-
-# This currently has little effect.
-check:
-	@echo "Tests are disabled. Configure without '--disable-tests', or avoid calling 'make check'."
-	@exit 1
--- a/mk/install-dirs.mk
+++ b/mk/install-dirs.mk
@ -0,0 +1,11 @@
+# Default installation paths.
+prefix ?= /usr/local
+libdir ?= $(prefix)/lib
+bindir ?= $(prefix)/bin
+libexecdir ?= $(prefix)/libexec
+datadir ?= $(prefix)/share
+localstatedir ?= $(prefix)/var
+sysconfdir ?= $(prefix)/etc
+mandir ?= $(prefix)/share/man
+
+DESTDIR ?=
--- a/mk/lib.mk
+++ b/mk/lib.mk
@ -12,24 +12,7 @@ man-pages :=
 install-tests :=
 install-tests-groups :=

-ifdef HOST_OS
-  HOST_KERNEL = $(firstword $(subst -, ,$(HOST_OS)))
-  ifeq ($(HOST_KERNEL), cygwin)
-    HOST_CYGWIN = 1
-  endif
-  ifeq ($(patsubst darwin%,,$(HOST_KERNEL)),)
-    HOST_DARWIN = 1
-  endif
-  ifeq ($(patsubst freebsd%,,$(HOST_KERNEL)),)
-    HOST_FREEBSD = 1
-  endif
-  ifeq ($(HOST_KERNEL), linux)
-    HOST_LINUX = 1
-  endif
-  ifeq ($(patsubst solaris%,,$(HOST_KERNEL)),)
-    HOST_SOLARIS = 1
-  endif
-endif
+include mk/platform.mk

 # Hack to define a literal space.
 space :=
@ -43,27 +26,6 @@ define newline
 endef


-# Default installation paths.
-prefix ?= /usr/local
-libdir ?= $(prefix)/lib
-bindir ?= $(prefix)/bin
-libexecdir ?= $(prefix)/libexec
-datadir ?= $(prefix)/share
-localstatedir ?= $(prefix)/var
-sysconfdir ?= $(prefix)/etc
-mandir ?= $(prefix)/share/man
-
-
-# Initialise support for build directories.
-builddir ?=
-
-ifdef builddir
-  buildprefix = $(builddir)/
-else
-  buildprefix =
-endif
-
-
 # Pass -fPIC if we're building dynamic libraries.
 BUILD_SHARED_LIBS ?= 1

@ -94,6 +56,8 @@ ifeq ($(BUILD_DEBUG), 1)
 endif


+include mk/build-dir.mk
+include mk/install-dirs.mk
 include mk/functions.mk
 include mk/tracing.mk
 include mk/clean.mk
--- a/mk/libraries.mk
+++ b/mk/libraries.mk
@ -3,13 +3,19 @@ libs-list :=
 ifdef HOST_DARWIN
  SO_EXT = dylib
 else
-  ifdef HOST_CYGWIN
+  ifdef HOST_WINDOWS
    SO_EXT = dll
  else
    SO_EXT = so
  endif
 endif

+ifdef HOST_UNIX
+  THREAD_LDFLAGS = -pthread
+else
+  THREAD_LDFLAGS =
+endif
+
 # Build a library with symbolic name $(1).  The library is defined by
 # various variables prefixed by ‘$(1)_’:
 #
@ -59,7 +65,7 @@ define build-library
  $(1)_OBJS := $$(addprefix $(buildprefix), $$(addsuffix .o, $$(basename $$(_srcs))))
  _libs := $$(foreach lib, $$($(1)_LIBS), $$($$(lib)_PATH))

-  ifdef HOST_CYGWIN
+  ifdef HOST_WINDOWS
    $(1)_INSTALL_DIR ?= $$(bindir)
  else
    $(1)_INSTALL_DIR ?= $$(libdir)
@ -79,7 +85,7 @@ define build-library
      endif
    else
      ifndef HOST_DARWIN
-        ifndef HOST_CYGWIN
+        ifndef HOST_WINDOWS
          $(1)_LDFLAGS += -Wl,-z,defs
        endif
      endif
--- a/mk/platform.mk
+++ b/mk/platform.mk
@ -0,0 +1,32 @@
+ifdef HOST_OS
+  HOST_KERNEL = $(firstword $(subst -, ,$(HOST_OS)))
+  ifeq ($(patsubst mingw%,,$(HOST_KERNEL)),)
+    HOST_MINGW = 1
+    HOST_WINDOWS = 1
+  endif
+  ifeq ($(HOST_KERNEL), cygwin)
+    HOST_CYGWIN = 1
+    HOST_WINDOWS = 1
+    HOST_UNIX = 1
+  endif
+  ifeq ($(patsubst darwin%,,$(HOST_KERNEL)),)
+    HOST_DARWIN = 1
+    HOST_UNIX = 1
+  endif
+  ifeq ($(patsubst freebsd%,,$(HOST_KERNEL)),)
+    HOST_FREEBSD = 1
+    HOST_UNIX = 1
+  endif
+  ifeq ($(patsubst netbsd%,,$(HOST_KERNEL)),)
+    HOST_NETBSD = 1
+    HOST_UNIX = 1
+  endif
+  ifeq ($(HOST_KERNEL), linux)
+    HOST_LINUX = 1
+    HOST_UNIX = 1
+  endif
+  ifeq ($(patsubst solaris%,,$(HOST_KERNEL)),)
+    HOST_SOLARIS = 1
+    HOST_UNIX = 1
+  endif
+endif
--- a/mk/programs.mk
+++ b/mk/programs.mk
@ -1,5 +1,11 @@
 programs-list :=

+ifdef HOST_WINDOWS
+  EXE_EXT = .exe
+else
+  EXE_EXT =
+endif
+
 # Build a program with symbolic name $(1).  The program is defined by
 # various variables prefixed by ‘$(1)_’:
 #
@ -31,7 +37,7 @@ define build-program
  _srcs := $$(sort $$(foreach src, $$($(1)_SOURCES), $$(src)))
  $(1)_OBJS := $$(addprefix $(buildprefix), $$(addsuffix .o, $$(basename $$(_srcs))))
  _libs := $$(foreach lib, $$($(1)_LIBS), $$(foreach lib2, $$($$(lib)_LIB_CLOSURE), $$($$(lib2)_PATH)))
-  $(1)_PATH := $$(_d)/$$($(1)_NAME)
+  $(1)_PATH := $$(_d)/$$($(1)_NAME)$(EXE_EXT)

  $$(eval $$(call create-dir, $$(_d)))

@ -42,7 +48,7 @@ define build-program

  ifdef $(1)_INSTALL_DIR

-    $(1)_INSTALL_PATH := $$($(1)_INSTALL_DIR)/$$($(1)_NAME)
+    $(1)_INSTALL_PATH := $$($(1)_INSTALL_DIR)/$$($(1)_NAME)$(EXE_EXT)

    $$(eval $$(call create-dir, $$($(1)_INSTALL_DIR)))

@ -87,6 +93,6 @@ define build-program
  # Phony target to run this program (typically as a dependency of 'check').
  .PHONY: $(1)_RUN
  $(1)_RUN: $$($(1)_PATH)
-	$(trace-test) $$(UNIT_TEST_ENV) $$($(1)_PATH)
+	$(trace-test) $$($(1)_ENV) $$($(1)_PATH)

 endef
--- a/mk/templates.mk
+++ b/mk/templates.mk
@ -10,10 +10,10 @@ endef

 ifneq ($(MAKECMDGOALS), clean)

-%.h: %.h.in
-	$(trace-gen) rm -f $@ && ./config.status --quiet --header=$@
+$(buildprefix)%.h: %.h.in
+	$(trace-gen) rm -f $@ && cd $(buildprefixrel) && ./config.status --quiet --header=$(@:$(buildprefix)%=%)

-%: %.in
-	$(trace-gen) rm -f $@ && ./config.status --quiet --file=$@
+$(buildprefix)%: %.in
+	$(trace-gen) rm -f $@ && cd $(buildprefixrel) && ./config.status --quiet --file=$(@:$(buildprefix)%=%)

 endif
--- a/package.nix
+++ b/package.nix
@ -0,0 +1,402 @@
+{ lib
+, stdenv
+, releaseTools
+, autoconf-archive
+, autoreconfHook
+, aws-sdk-cpp
+, boehmgc
+, nlohmann_json
+, bison
+, boost
+, brotli
+, bzip2
+, changelog-d
+, curl
+, editline
+, readline
+, fileset
+, flex
+, git
+, gtest
+, jq
+, doxygen
+, libarchive
+, libcpuid
+, libgit2
+, libseccomp
+, libsodium
+, lowdown
+, mdbook
+, mdbook-linkcheck
+, mercurial
+, openssh
+, openssl
+, pkg-config
+, rapidcheck
+, sqlite
+, util-linux
+, xz
+
+, busybox-sandbox-shell ? null
+
+# Configuration Options
+#:
+# This probably seems like too many degrees of freedom, but it
+# faithfully reflects how the underlying configure + make build system
+# work. The top-level flake.nix will choose useful combinations of these
+# options to CI.
+
+, pname ? "nix"
+
+, versionSuffix ? ""
+, officialRelease ? false
+
+# Whether to build Nix. Useful to skip for tasks like (a) just
+# generating API docs or (b) testing existing pre-built versions of Nix
+, doBuild ? true
+
+# Run the unit tests as part of the build. See `installUnitTests` for an
+# alternative to this.
+, doCheck ? __forDefaults.canRunInstalled
+
+# Run the functional tests as part of the build.
+, doInstallCheck ? test-client != null || __forDefaults.canRunInstalled
+
+# Check test coverage of Nix. Probably want to use with with at least
+# one of `doCHeck` or `doInstallCheck` enabled.
+, withCoverageChecks ? false
+
+# Whether to build the regular manual
+, enableManual ? __forDefaults.canRunInstalled
+
+# Whether to use garbage collection for the Nix language evaluator.
+#
+# If it is disabled, we just leak memory, but this is not as bad as it
+# sounds so long as evaluation just takes places within short-lived
+# processes. (When the process exits, the memory is reclaimed; it is
+# only leaked *within* the process.)
+, enableGC ? true
+
+# Whether to enable Markdown rendering in the Nix binary.
+, enableMarkdown ? !stdenv.hostPlatform.isWindows
+
+# Which interactive line editor library to use for Nix's repl.
+#
+# Currently supported choices are:
+#
+# - editline (default)
+# - readline
+, readlineFlavor ? if stdenv.hostPlatform.isWindows then "readline" else "editline"
+
+# Whether to compile `rl-next.md`, the release notes for the next
+# not-yet-released version of Nix in the manul, from the individual
+# change log entries in the directory.
+, buildUnreleasedNotes ? false
+
+# Whether to build the internal API docs, can be done separately from
+# everything else.
+, enableInternalAPIDocs ? false
+
+# Whether to install unit tests. This is useful when cross compiling
+# since we cannot run them natively during the build, but can do so
+# later.
+, installUnitTests ? doBuild && !__forDefaults.canExecuteHost
+
+# For running the functional tests against a pre-built Nix. Probably
+# want to use in conjunction with `doBuild = false;`.
+, test-daemon ? null
+, test-client ? null
+
+# Avoid setting things that would interfere with a functioning devShell
+, forDevShell ? false
+
+# Not a real argument, just the only way to approximate let-binding some
+# stuff for argument defaults.
+, __forDefaults ? {
+    canExecuteHost = stdenv.buildPlatform.canExecute stdenv.hostPlatform;
+    canRunInstalled = doBuild && __forDefaults.canExecuteHost;
+  }
+}:
+
+let
+  version = lib.fileContents ./.version + versionSuffix;
+
+  # selected attributes with defaults, will be used to define some
+  # things which should instead be gotten via `finalAttrs` in order to
+  # work with overriding.
+  attrs = {
+    inherit doBuild doCheck doInstallCheck;
+  };
+
+  mkDerivation =
+    if withCoverageChecks
+    then
+      # TODO support `finalAttrs` args function in
+      # `releaseTools.coverageAnalysis`.
+      argsFun:
+         releaseTools.coverageAnalysis (let args = argsFun args; in args)
+    else stdenv.mkDerivation;
+in
+
+mkDerivation (finalAttrs: let
+
+  inherit (finalAttrs)
+    doCheck
+    doInstallCheck
+    ;
+
+  doBuild = !finalAttrs.dontBuild;
+
+  # Either running the unit tests during the build, or installing them
+  # to be run later, requiresthe unit tests to be built.
+  buildUnitTests = doCheck || installUnitTests;
+
+in {
+  inherit pname version;
+
+  src =
+    let
+      baseFiles = fileset.fileFilter (f: f.name != ".gitignore") ./.;
+    in
+      fileset.toSource {
+        root = ./.;
+        fileset = fileset.intersect baseFiles (fileset.unions ([
+          # For configure
+          ./.version
+          ./configure.ac
+          ./m4
+          # TODO: do we really need README.md? It doesn't seem used in the build.
+          ./README.md
+          # For make, regardless of what we are building
+          ./local.mk
+          ./Makefile
+          ./Makefile.config.in
+          ./mk
+          (fileset.fileFilter (f: lib.strings.hasPrefix "nix-profile" f.name) ./scripts)
+        ] ++ lib.optionals doBuild [
+          ./doc
+          ./misc
+          ./precompiled-headers.h
+          ./src
+          ./COPYING
+          ./scripts/local.mk
+        ] ++ lib.optionals buildUnitTests [
+          ./doc/manual
+        ] ++ lib.optionals enableInternalAPIDocs [
+          ./doc/internal-api
+          # Source might not be compiled, but still must be available
+          # for Doxygen to gather comments.
+          ./src
+          ./tests/unit
+        ] ++ lib.optionals buildUnitTests [
+          ./tests/unit
+        ] ++ lib.optionals doInstallCheck [
+          ./tests/functional
+        ]));
+      };
+
+  VERSION_SUFFIX = versionSuffix;
+
+  outputs = [ "out" ]
+    ++ lib.optional doBuild "dev"
+    # If we are doing just build or just docs, the one thing will use
+    # "out". We only need additional outputs if we are doing both.
+    ++ lib.optional (doBuild && (enableManual || enableInternalAPIDocs)) "doc"
+    ++ lib.optional installUnitTests "check";
+
+  nativeBuildInputs = [
+    autoconf-archive
+    autoreconfHook
+    pkg-config
+  ] ++ lib.optionals doBuild [
+    bison
+    flex
+  ] ++ lib.optionals enableManual [
+    (lib.getBin lowdown)
+    mdbook
+    mdbook-linkcheck
+  ] ++ lib.optionals (doInstallCheck || enableManual) [
+    jq # Also for custom mdBook preprocessor.
+  ] ++ lib.optional stdenv.hostPlatform.isLinux util-linux
+    # Official releases don't have rl-next, so we don't need to compile a
+    # changelog
+    ++ lib.optional (!officialRelease && buildUnreleasedNotes) changelog-d
+    ++ lib.optional enableInternalAPIDocs doxygen
+  ;
+
+  buildInputs = lib.optionals doBuild [
+    boost
+    brotli
+    bzip2
+    curl
+    libarchive
+    libgit2
+    libsodium
+    openssl
+    sqlite
+    xz
+    ({ inherit readline editline; }.${readlineFlavor})
+  ] ++ lib.optionals enableMarkdown [
+    lowdown
+  ] ++ lib.optionals buildUnitTests [
+    gtest
+    rapidcheck
+  ] ++ lib.optional stdenv.isLinux libseccomp
+    ++ lib.optional stdenv.hostPlatform.isx86_64 libcpuid
+    # There have been issues building these dependencies
+    ++ lib.optional (stdenv.hostPlatform == stdenv.buildPlatform && (stdenv.isLinux || stdenv.isDarwin))
+      (aws-sdk-cpp.override {
+        apis = ["s3" "transfer"];
+        customMemoryManagement = false;
+      })
+  ;
+
+  propagatedBuildInputs = [
+    nlohmann_json
+  ] ++ lib.optional enableGC boehmgc;
+
+  dontBuild = !attrs.doBuild;
+  doCheck = attrs.doCheck;
+
+  nativeCheckInputs = [
+    git
+    mercurial
+    openssh
+  ];
+
+  disallowedReferences = [ boost ];
+
+  preConfigure = lib.optionalString (doBuild && ! stdenv.hostPlatform.isStatic) (
+    ''
+      # Copy libboost_context so we don't get all of Boost in our closure.
+      # https://github.com/NixOS/nixpkgs/issues/45462
+      mkdir -p $out/lib
+      cp -pd ${boost}/lib/{libboost_context*,libboost_thread*,libboost_system*} $out/lib
+      rm -f $out/lib/*.a
+    '' + lib.optionalString stdenv.hostPlatform.isLinux ''
+      chmod u+w $out/lib/*.so.*
+      patchelf --set-rpath $out/lib:${stdenv.cc.cc.lib}/lib $out/lib/libboost_thread.so.*
+    '' + lib.optionalString stdenv.hostPlatform.isDarwin ''
+      for LIB in $out/lib/*.dylib; do
+        chmod u+w $LIB
+        install_name_tool -id $LIB $LIB
+        install_name_tool -delete_rpath ${boost}/lib/ $LIB || true
+      done
+      install_name_tool -change ${boost}/lib/libboost_system.dylib $out/lib/libboost_system.dylib $out/lib/libboost_thread.dylib
+    ''
+  );
+
+  configureFlags = [
+    (lib.enableFeature doBuild "build")
+    (lib.enableFeature buildUnitTests "unit-tests")
+    (lib.enableFeature doInstallCheck "functional-tests")
+    (lib.enableFeature enableInternalAPIDocs "internal-api-docs")
+    (lib.enableFeature enableManual "doc-gen")
+    (lib.enableFeature enableGC "gc")
+    (lib.enableFeature enableMarkdown "markdown")
+    (lib.enableFeature installUnitTests "install-unit-tests")
+    (lib.withFeatureAs true "readline-flavor" readlineFlavor)
+  ] ++ lib.optionals (!forDevShell) [
+    "--sysconfdir=/etc"
+  ] ++ lib.optionals installUnitTests [
+    "--with-check-bin-dir=${builtins.placeholder "check"}/bin"
+    "--with-check-lib-dir=${builtins.placeholder "check"}/lib"
+  ] ++ lib.optionals (doBuild) [
+    "--with-boost=${boost}/lib"
+  ] ++ lib.optionals (doBuild && stdenv.isLinux) [
+    "--with-sandbox-shell=${busybox-sandbox-shell}/bin/busybox"
+  ] ++ lib.optional (doBuild && stdenv.isLinux && !(stdenv.hostPlatform.isStatic && stdenv.system == "aarch64-linux"))
+       "LDFLAGS=-fuse-ld=gold"
+    ++ lib.optional (doBuild && stdenv.hostPlatform.isStatic) "--enable-embedded-sandbox-shell"
+    ;
+
+  enableParallelBuilding = true;
+
+  makeFlags = "profiledir=$(out)/etc/profile.d PRECOMPILE_HEADERS=1";
+
+  installTargets = lib.optional doBuild "install"
+    ++ lib.optional enableInternalAPIDocs "internal-api-html";
+
+  installFlags = "sysconfdir=$(out)/etc";
+
+  # In this case we are probably just running tests, and so there isn't
+  # anything to install, we just make an empty directory to signify tests
+  # succeeded.
+  installPhase = if finalAttrs.installTargets != [] then null else ''
+    mkdir -p $out
+  '';
+
+  postInstall = lib.optionalString doBuild (
+    lib.optionalString stdenv.hostPlatform.isStatic ''
+      mkdir -p $out/nix-support
+      echo "file binary-dist $out/bin/nix" >> $out/nix-support/hydra-build-products
+    '' + lib.optionalString stdenv.isDarwin ''
+      install_name_tool \
+      -change ${boost}/lib/libboost_context.dylib \
+      $out/lib/libboost_context.dylib \
+      $out/lib/libnixutil.dylib
+    ''
+  ) + lib.optionalString enableManual ''
+    mkdir -p ''${!outputDoc}/nix-support
+    echo "doc manual ''${!outputDoc}/share/doc/nix/manual" >> ''${!outputDoc}/nix-support/hydra-build-products
+  '' + lib.optionalString enableInternalAPIDocs ''
+    mkdir -p ''${!outputDoc}/nix-support
+    echo "doc internal-api-docs $out/share/doc/nix/internal-api/html" >> ''${!outputDoc}/nix-support/hydra-build-products
+  '';
+
+  doInstallCheck = attrs.doInstallCheck;
+
+  installCheckFlags = "sysconfdir=$(out)/etc";
+  # Work around buggy detection in stdenv.
+  installCheckTarget = "installcheck";
+
+  # Work around weird bug where it doesn't think there is a Makefile.
+  installCheckPhase = if (!doBuild && doInstallCheck) then ''
+    mkdir -p src/nix-channel
+    make installcheck -j$NIX_BUILD_CORES -l$NIX_BUILD_CORES
+  '' else null;
+
+  # Needed for tests if we are not doing a build, but testing existing
+  # built Nix.
+  preInstallCheck = lib.optionalString (! doBuild) ''
+    mkdir -p src/nix-channel
+  '';
+
+  separateDebugInfo = !stdenv.hostPlatform.isStatic;
+
+  # TODO `releaseTools.coverageAnalysis` in Nixpkgs needs to be updated
+  # to work with `strictDeps`.
+  strictDeps = !withCoverageChecks;
+
+  hardeningDisable = lib.optional stdenv.hostPlatform.isStatic "pie";
+
+  meta = {
+    platforms = lib.platforms.unix ++ lib.platforms.windows;
+    mainProgram = "nix";
+    broken = !(lib.all (a: a) [
+      # We cannot run or install unit tests if we don't build them or
+      # Nix proper (which they depend on).
+      (installUnitTests -> doBuild)
+      (doCheck -> doBuild)
+      # We have to build the manual to build unreleased notes, as those
+      # are part of the manual
+      (buildUnreleasedNotes -> enableManual)
+      # The build process for the manual currently requires extracting
+      # data from the Nix executable we are trying to document.
+      (enableManual -> doBuild)
+    ]);
+  };
+
+} // lib.optionalAttrs withCoverageChecks {
+  lcovFilter = [ "*/boost/*" "*-tab.*" ];
+
+  hardeningDisable = ["fortify"];
+
+  NIX_CFLAGS_COMPILE = "-DCOVERAGE=1";
+
+  dontInstall = false;
+} // lib.optionalAttrs (test-daemon != null) {
+  NIX_DAEMON_PACKAGE = test-daemon;
+} // lib.optionalAttrs (test-client != null) {
+  NIX_CLIENT_PACKAGE = test-client;
+})
--- a/perl/lib/Nix/Store.xs
+++ b/perl/lib/Nix/Store.xs
@ -9,9 +9,10 @@
 #undef do_close

 #include "derivations.hh"
+#include "realisation.hh"
 #include "globals.hh"
 #include "store-api.hh"
-#include "crypto.hh"
+#include "posix-source-accessor.hh"

 #include <sodium.h>
 #include <nlohmann/json.hpp>
@ -77,7 +78,7 @@ SV * queryReferences(char * path)
 SV * queryPathHash(char * path)
    PPCODE:
        try {
-            auto s = store()->queryPathInfo(store()->parseStorePath(path))->narHash.to_string(HashFormat::Base32, true);
+            auto s = store()->queryPathInfo(store()->parseStorePath(path))->narHash.to_string(HashFormat::Nix32, true);
            XPUSHs(sv_2mortal(newSVpv(s.c_str(), 0)));
        } catch (Error & e) {
            croak("%s", e.what());
@ -103,7 +104,7 @@ SV * queryPathInfo(char * path, int base32)
                XPUSHs(&PL_sv_undef);
            else
                XPUSHs(sv_2mortal(newSVpv(store()->printStorePath(*info->deriver).c_str(), 0)));
-            auto s = info->narHash.to_string(base32 ? HashFormat::Base32 : HashFormat::Base16, true);
+            auto s = info->narHash.to_string(base32 ? HashFormat::Nix32 : HashFormat::Base16, true);
            XPUSHs(sv_2mortal(newSVpv(s.c_str(), 0)));
            mXPUSHi(info->registrationTime);
            mXPUSHi(info->narSize);
@ -204,8 +205,11 @@ void importPaths(int fd, int dontCheckSigs)
 SV * hashPath(char * algo, int base32, char * path)
    PPCODE:
        try {
-            Hash h = hashPath(parseHashType(algo), path).first;
-            auto s = h.to_string(base32 ? HashFormat::Base32 : HashFormat::Base16, false);
+            PosixSourceAccessor accessor;
+            Hash h = hashPath(
+                accessor, CanonPath::fromCwd(path),
+                FileIngestionMethod::Recursive, parseHashAlgo(algo)).first;
+            auto s = h.to_string(base32 ? HashFormat::Nix32 : HashFormat::Base16, false);
            XPUSHs(sv_2mortal(newSVpv(s.c_str(), 0)));
        } catch (Error & e) {
            croak("%s", e.what());
@ -215,8 +219,8 @@ SV * hashPath(char * algo, int base32, char * path)
 SV * hashFile(char * algo, int base32, char * path)
    PPCODE:
        try {
-            Hash h = hashFile(parseHashType(algo), path);
-            auto s = h.to_string(base32 ? HashFormat::Base32 : HashFormat::Base16, false);
+            Hash h = hashFile(parseHashAlgo(algo), path);
+            auto s = h.to_string(base32 ? HashFormat::Nix32 : HashFormat::Base16, false);
            XPUSHs(sv_2mortal(newSVpv(s.c_str(), 0)));
        } catch (Error & e) {
            croak("%s", e.what());
@ -226,8 +230,8 @@ SV * hashFile(char * algo, int base32, char * path)
 SV * hashString(char * algo, int base32, char * s)
    PPCODE:
        try {
-            Hash h = hashString(parseHashType(algo), s);
-            auto s = h.to_string(base32 ? HashFormat::Base32 : HashFormat::Base16, false);
+            Hash h = hashString(parseHashAlgo(algo), s);
+            auto s = h.to_string(base32 ? HashFormat::Nix32 : HashFormat::Base16, false);
            XPUSHs(sv_2mortal(newSVpv(s.c_str(), 0)));
        } catch (Error & e) {
            croak("%s", e.what());
@ -237,8 +241,8 @@ SV * hashString(char * algo, int base32, char * s)
 SV * convertHash(char * algo, char * s, int toBase32)
    PPCODE:
        try {
-            auto h = Hash::parseAny(s, parseHashType(algo));
-            auto s = h.to_string(toBase32 ? HashFormat::Base32 : HashFormat::Base16, false);
+            auto h = Hash::parseAny(s, parseHashAlgo(algo));
+            auto s = h.to_string(toBase32 ? HashFormat::Nix32 : HashFormat::Base16, false);
            XPUSHs(sv_2mortal(newSVpv(s.c_str(), 0)));
        } catch (Error & e) {
            croak("%s", e.what());
@ -280,7 +284,11 @@ SV * addToStore(char * srcPath, int recursive, char * algo)
    PPCODE:
        try {
            auto method = recursive ? FileIngestionMethod::Recursive : FileIngestionMethod::Flat;
-            auto path = store()->addToStore(std::string(baseNameOf(srcPath)), srcPath, method, parseHashType(algo));
+            PosixSourceAccessor accessor;
+            auto path = store()->addToStore(
+                std::string(baseNameOf(srcPath)),
+                accessor, CanonPath::fromCwd(srcPath),
+                method, parseHashAlgo(algo));
            XPUSHs(sv_2mortal(newSVpv(store()->printStorePath(path).c_str(), 0)));
        } catch (Error & e) {
            croak("%s", e.what());
@ -290,7 +298,7 @@ SV * addToStore(char * srcPath, int recursive, char * algo)
 SV * makeFixedOutputPath(int recursive, char * algo, char * hash, char * name)
    PPCODE:
        try {
-            auto h = Hash::parseAny(hash, parseHashType(algo));
+            auto h = Hash::parseAny(hash, parseHashAlgo(algo));
            auto method = recursive ? FileIngestionMethod::Recursive : FileIngestionMethod::Flat;
            auto path = store()->makeFixedOutputPath(name, FixedOutputInfo {
                .method = method,
--- a/scripts/binary-tarball.nix
+++ b/scripts/binary-tarball.nix
@ -0,0 +1,84 @@
+{ runCommand
+, system
+, buildPackages
+, cacert
+, nix
+}:
+
+let
+
+  installerClosureInfo = buildPackages.closureInfo {
+    rootPaths = [ nix cacert ];
+  };
+
+  inherit (nix) version;
+
+  env = {
+    #nativeBuildInputs = lib.optional (system != "aarch64-linux") shellcheck;
+    meta.description = "Distribution-independent Nix bootstrap binaries for ${system}";
+  };
+
+in
+
+runCommand "nix-binary-tarball-${version}" env ''
+  cp ${installerClosureInfo}/registration $TMPDIR/reginfo
+  cp ${./create-darwin-volume.sh} $TMPDIR/create-darwin-volume.sh
+  substitute ${./install-nix-from-closure.sh} $TMPDIR/install \
+    --subst-var-by nix ${nix} \
+    --subst-var-by cacert ${cacert}
+
+  substitute ${./install-darwin-multi-user.sh} $TMPDIR/install-darwin-multi-user.sh \
+    --subst-var-by nix ${nix} \
+    --subst-var-by cacert ${cacert}
+  substitute ${./install-systemd-multi-user.sh} $TMPDIR/install-systemd-multi-user.sh \
+    --subst-var-by nix ${nix} \
+    --subst-var-by cacert ${cacert}
+  substitute ${./install-multi-user.sh} $TMPDIR/install-multi-user \
+    --subst-var-by nix ${nix} \
+    --subst-var-by cacert ${cacert}
+
+  if type -p shellcheck; then
+    # SC1090: Don't worry about not being able to find
+    #         $nix/etc/profile.d/nix.sh
+    shellcheck --exclude SC1090 $TMPDIR/install
+    shellcheck $TMPDIR/create-darwin-volume.sh
+    shellcheck $TMPDIR/install-darwin-multi-user.sh
+    shellcheck $TMPDIR/install-systemd-multi-user.sh
+
+    # SC1091: Don't panic about not being able to source
+    #         /etc/profile
+    # SC2002: Ignore "useless cat" "error", when loading
+    #         .reginfo, as the cat is a much cleaner
+    #         implementation, even though it is "useless"
+    # SC2116: Allow ROOT_HOME=$(echo ~root) for resolving
+    #         root's home directory
+    shellcheck --external-sources \
+      --exclude SC1091,SC2002,SC2116 $TMPDIR/install-multi-user
+  fi
+
+  chmod +x $TMPDIR/install
+  chmod +x $TMPDIR/create-darwin-volume.sh
+  chmod +x $TMPDIR/install-darwin-multi-user.sh
+  chmod +x $TMPDIR/install-systemd-multi-user.sh
+  chmod +x $TMPDIR/install-multi-user
+  dir=nix-${version}-${system}
+  fn=$out/$dir.tar.xz
+  mkdir -p $out/nix-support
+  echo "file binary-dist $fn" >> $out/nix-support/hydra-build-products
+  tar cvfJ $fn \
+    --owner=0 --group=0 --mode=u+rw,uga+r \
+    --mtime='1970-01-01' \
+    --absolute-names \
+    --hard-dereference \
+    --transform "s,$TMPDIR/install,$dir/install," \
+    --transform "s,$TMPDIR/create-darwin-volume.sh,$dir/create-darwin-volume.sh," \
+    --transform "s,$TMPDIR/reginfo,$dir/.reginfo," \
+    --transform "s,$NIX_STORE,$dir/store,S" \
+    $TMPDIR/install \
+    $TMPDIR/create-darwin-volume.sh \
+    $TMPDIR/install-darwin-multi-user.sh \
+    $TMPDIR/install-systemd-multi-user.sh \
+    $TMPDIR/install-multi-user \
+    $TMPDIR/reginfo \
+    $(cat ${installerClosureInfo}/store-paths)
+''
--- a/scripts/install-darwin-multi-user.sh
+++ b/scripts/install-darwin-multi-user.sh
@ -3,11 +3,13 @@
 set -eu
 set -o pipefail

+# System specific settings
+export NIX_FIRST_BUILD_UID="${NIX_FIRST_BUILD_UID:-301}"
+export NIX_BUILD_USER_NAME_TEMPLATE="_nixbld%d"
+
 readonly NIX_DAEMON_DEST=/Library/LaunchDaemons/org.nixos.nix-daemon.plist
 # create by default; set 0 to DIY, use a symlink, etc.
 readonly NIX_VOLUME_CREATE=${NIX_VOLUME_CREATE:-1} # now default
-NIX_FIRST_BUILD_UID="301"
-NIX_BUILD_USER_NAME_TEMPLATE="_nixbld%d"

 # caution: may update times on / if not run as normal non-root user
 read_only_root() {
--- a/scripts/install-multi-user.sh
+++ b/scripts/install-multi-user.sh
@ -25,9 +25,9 @@ readonly RED='\033[31m'
 readonly NIX_USER_COUNT=${NIX_USER_COUNT:-32}
 readonly NIX_BUILD_GROUP_ID="${NIX_BUILD_GROUP_ID:-30000}"
 readonly NIX_BUILD_GROUP_NAME="nixbld"
-# darwin installer needs to override these
-NIX_FIRST_BUILD_UID="${NIX_FIRST_BUILD_UID:-30001}"
-NIX_BUILD_USER_NAME_TEMPLATE="nixbld%d"
+# each system specific installer must set these:
+#   NIX_FIRST_BUILD_UID
+#   NIX_BUILD_USER_NAME_TEMPLATE
 # Please don't change this. We don't support it, because the
 # default shell profile that comes with Nix doesn't support it.
 readonly NIX_ROOT="/nix"
@ -707,6 +707,12 @@ EOF
    fi
 }

+check_required_system_specific_settings() {
+    if [ -z "${NIX_FIRST_BUILD_UID+x}" ] || [ -z "${NIX_BUILD_USER_NAME_TEMPLATE+x}" ]; then
+        failure "Internal error: System specific installer for $(uname) ($1) does not export required settings."
+    fi
+}
+
 welcome_to_nix() {
    local -r NIX_UID_RANGES="${NIX_FIRST_BUILD_UID}..$((NIX_FIRST_BUILD_UID + NIX_USER_COUNT - 1))"
    local -r RANGE_TEXT=$(echo -ne "${BLUE}(uids [${NIX_UID_RANGES}])${ESC}")
@ -726,7 +732,9 @@ manager. This will happen in a few stages:
   if you are ready to continue.

 3. Create the system users ${RANGE_TEXT} and groups ${GROUP_TEXT}
-   that the Nix daemon uses to run builds.
+   that the Nix daemon uses to run builds. To create system users
+   in a different range, exit and run this tool again with
+   NIX_FIRST_BUILD_UID set.

 4. Perform the basic installation of the Nix files daemon.

@ -968,13 +976,16 @@ main() {
    if is_os_darwin; then
        # shellcheck source=./install-darwin-multi-user.sh
        . "$EXTRACTED_NIX_PATH/install-darwin-multi-user.sh"
+        check_required_system_specific_settings "install-darwin-multi-user.sh"
    elif is_os_linux; then
        # shellcheck source=./install-systemd-multi-user.sh
        . "$EXTRACTED_NIX_PATH/install-systemd-multi-user.sh" # most of this works on non-systemd distros also
+        check_required_system_specific_settings "install-systemd-multi-user.sh"
    else
        failure "Sorry, I don't know what to do on $(uname)"
    fi

+
    welcome_to_nix

    if ! is_root; then
--- a/scripts/install-systemd-multi-user.sh
+++ b/scripts/install-systemd-multi-user.sh
@ -3,6 +3,10 @@
 set -eu
 set -o pipefail

+# System specific settings
+export NIX_FIRST_BUILD_UID="${NIX_FIRST_BUILD_UID:-30001}"
+export NIX_BUILD_USER_NAME_TEMPLATE="nixbld%d"
+
 readonly SERVICE_SRC=/lib/systemd/system/nix-daemon.service
 readonly SERVICE_DEST=/etc/systemd/system/nix-daemon.service

--- a/scripts/installer.nix
+++ b/scripts/installer.nix
@ -0,0 +1,36 @@
+{ lib
+, runCommand
+, nix
+, tarballs
+}:
+
+runCommand "installer-script" {
+  buildInputs = [ nix ];
+} ''
+  mkdir -p $out/nix-support
+
+  # Converts /nix/store/50p3qk8k...-nix-2.4pre20201102_550e11f/bin/nix to 50p3qk8k.../bin/nix.
+  tarballPath() {
+    # Remove the store prefix
+    local path=''${1#${builtins.storeDir}/}
+    # Get the path relative to the derivation root
+    local rest=''${path#*/}
+    # Get the derivation hash
+    local drvHash=''${path%%-*}
+    echo "$drvHash/$rest"
+  }
+
+  substitute ${./install.in} $out/install \
+    ${lib.concatMapStrings
+      (tarball: let
+          inherit (tarball.stdenv.hostPlatform) system;
+        in '' \
+        --replace '@tarballHash_${system}@' $(nix --experimental-features nix-command hash-file --base16 --type sha256 ${tarball}/*.tar.xz) \
+        --replace '@tarballPath_${system}@' $(tarballPath ${tarball}/*.tar.xz) \
+        ''
+      )
+      tarballs
+    } --replace '@nixVersion@' ${nix.version}
+
+  echo "file installer $out/install" >> $out/nix-support/hydra-build-products
+''
--- a/scripts/nix-profile-daemon.sh.in
+++ b/scripts/nix-profile-daemon.sh.in
@ -31,7 +31,7 @@ fi
 export NIX_PROFILES="@localstatedir@/nix/profiles/default $NIX_LINK"

 # Populate bash completions, .desktop files, etc
-if [ -z "$XDG_DATA_DIRS" ]; then
+if [ -z "${XDG_DATA_DIRS-}" ]; then
    # According to XDG spec the default is /usr/local/share:/usr/share, don't set something that prevents that default
    export XDG_DATA_DIRS="/usr/local/share:/usr/share:$NIX_LINK/share:/nix/var/nix/profiles/default/share"
 else
--- a/scripts/nix-profile.sh.in
+++ b/scripts/nix-profile.sh.in
@ -33,7 +33,7 @@ if [ -n "$HOME" ] && [ -n "$USER" ]; then
    export NIX_PROFILES="@localstatedir@/nix/profiles/default $NIX_LINK"

    # Populate bash completions, .desktop files, etc
-    if [ -z "$XDG_DATA_DIRS" ]; then
+    if [ -z "${XDG_DATA_DIRS-}" ]; then
        # According to XDG spec the default is /usr/local/share:/usr/share, don't set something that prevents that default
        export XDG_DATA_DIRS="/usr/local/share:/usr/share:$NIX_LINK/share:/nix/var/nix/profiles/default/share"
    else
--- a/src/libcmd/built-path.cc
+++ b/src/libcmd/built-path.cc
@ -12,9 +12,9 @@ namespace nix {
    bool MY_TYPE ::operator COMPARATOR (const MY_TYPE & other) const \
    { \
        const MY_TYPE* me = this; \
-        auto fields1 = std::make_tuple<const CHILD_TYPE &, const FIELD_TYPE &>(*me->drvPath, me->FIELD); \
+        auto fields1 = std::tie(*me->drvPath, me->FIELD); \
        me = &other; \
-        auto fields2 = std::make_tuple<const CHILD_TYPE &, const FIELD_TYPE &>(*me->drvPath, me->FIELD); \
+        auto fields2 = std::tie(*me->drvPath, me->FIELD); \
        return fields1 COMPARATOR fields2; \
    }
 #define CMP(CHILD_TYPE, MY_TYPE, FIELD) \
@ -80,7 +80,7 @@ SingleDerivedPath SingleBuiltPath::discardOutputPath() const
    );
 }

-nlohmann::json BuiltPath::Built::toJSON(const Store & store) const
+nlohmann::json BuiltPath::Built::toJSON(const StoreDirConfig & store) const
 {
    nlohmann::json res;
    res["drvPath"] = drvPath->toJSON(store);
@ -90,7 +90,7 @@ nlohmann::json BuiltPath::Built::toJSON(const Store & store) const
    return res;
 }

-nlohmann::json SingleBuiltPath::Built::toJSON(const Store & store) const
+nlohmann::json SingleBuiltPath::Built::toJSON(const StoreDirConfig & store) const
 {
    nlohmann::json res;
    res["drvPath"] = drvPath->toJSON(store);
@ -100,14 +100,14 @@ nlohmann::json SingleBuiltPath::Built::toJSON(const Store & store) const
    return res;
 }

-nlohmann::json SingleBuiltPath::toJSON(const Store & store) const
+nlohmann::json SingleBuiltPath::toJSON(const StoreDirConfig & store) const
 {
    return std::visit([&](const auto & buildable) {
        return buildable.toJSON(store);
    }, raw());
 }

-nlohmann::json BuiltPath::toJSON(const Store & store) const
+nlohmann::json BuiltPath::toJSON(const StoreDirConfig & store) const
 {
    return std::visit([&](const auto & buildable) {
        return buildable.toJSON(store);
--- a/Show More
+++ b/Show More
 @ -1 +1 @@
 .19.0
 .20.0