Remove custom lowdown

This was last upgraded in 788008385e, but
the version in Nixpkgs is a now a lot newer. I think the custom was
added to get ahead of Nixpkgs before, and so now that we are in fact
behind, it is no longer needed.

flake.lock

@@ -32,22 +32,6 @@
         "type": "github"
       }
     },
-    "lowdown-src": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1633514407,
-        "narHash": "sha256-Dw32tiMjdK9t3ETl5fzGrutQTzh2rufgZV4A/BbxuD4=",
-        "owner": "kristapsdz",
-        "repo": "lowdown",
-        "rev": "d2c2b44ff6c27b936ec27358a2653caaef8f73b8",
-        "type": "github"
-      },
-      "original": {
-        "owner": "kristapsdz",
-        "repo": "lowdown",
-        "type": "github"
-      }
-    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1701355166,
@@ -84,7 +68,6 @@
       "inputs": {
         "flake-compat": "flake-compat",
         "libgit2": "libgit2",
-        "lowdown-src": "lowdown-src",
         "nixpkgs": "nixpkgs",
         "nixpkgs-regression": "nixpkgs-regression"
       }

flake.nix

@@ -13,11 +13,10 @@
   # to remove the `nix.checkAllErrors = false;` line in the tests.
   inputs.nixpkgs.url = "github:NixOS/nixpkgs/staging-23.05";
   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, libgit2, ... }:
+  outputs = { self, nixpkgs, nixpkgs-regression, libgit2, ... }:
 
     let
       inherit (nixpkgs) lib;
@@ -140,9 +139,6 @@
         {
           nixStable = prev.nix;
 
-          # Forward from the previous stage as we don’t want it to pick the lowdown override
-          inherit (prev) nixUnstable;
-
           default-busybox-sandbox-shell = final.busybox.override {
             useMusl = true;
             enableStatic = true;
@@ -167,10 +163,6 @@
             '';
           };
 
-          lowdown-nix = final.callPackage ./misc/lowdown.nix {
-            inherit lowdown-src stdenv;
-          };
-
           libgit2-nix = final.libgit2.overrideAttrs (attrs: {
             src = libgit2;
             version = libgit2.lastModifiedDate;
@@ -208,7 +200,6 @@
               officialRelease = false;
               boehmgc = final.boehmgc-nix;
               libgit2 = final.libgit2-nix;
-              lowdown = final.lowdown-nix;
               busybox-sandbox-shell = final.busybox-sandbox-shell or final.default-busybox-sandbox-shell;
               changelog-d = final.changelog-d-nix;
             } // {

misc/lowdown.nix

@@ -1,22 +0,0 @@
-{ lib
-, stdenv
-, which
-, lowdown-src
-}:
-
-stdenv.mkDerivation rec {
-  name = "lowdown-0.9.0";
-
-  src = lowdown-src;
-
-  outputs = [ "out" "bin" "dev" ];
-
-  nativeBuildInputs = [ which ];
-
-  configurePhase = ''
-      ${lib.optionalString (stdenv.isDarwin && stdenv.isAarch64) "echo \"HAVE_SANDBOX_INIT=false\" > configure.local"}
-      ./configure \
-        PREFIX=${placeholder "dev"} \
-        BINDIR=${placeholder "bin"}/bin
-  '';
-}