nixpkgs/pkgs/build-support/writers/scripts.nix

{
  buildPackages,
  gixy,
  lib,
  libiconv,
  makeBinaryWrapper,
  mkNugetDeps,
  mkNugetSource,
  pkgs,
  stdenv,
}:
let
  inherit (lib)
    concatMapStringsSep
    elem
    escapeShellArg
    last
    optionalString
    strings
    types
    ;
in
rec {
  /**
    `makeScriptWriter` returns a derivation which creates an executable script.

    # Inputs

    config (AttrSet)
    : `interpreter` (String)
      : the [interpreter](https://en.wikipedia.org/wiki/Shebang_(Unix)) to use for the script.
    : `check` (String)
      : A command to check the script. For example, this could be a linting check.
    : `makeWrapperArgs` (Optional, [ String ], Default: [])
      : Arguments forwarded to (`makeWrapper`)[#fun-makeWrapper].

    `nameOrPath` (String)
    : The name of the script or the path to the script.

      When a `string` starting with "/" is passed, the script will be created at the specified path in $out.
      I.e. `"/bin/hello"` will create a script at `$out/bin/hello`.

      Any other `string` is interpreted as a filename.
      It must be a [POSIX filename](https://en.wikipedia.org/wiki/Filename) starting with a letter, digit, dot, or underscore.
      Spaces or special characters are not allowed.

    `content` (String)
    : The content of the script.

    :::{.note}
    This function is used as base implementation for other high-level writer functions.

    For example, `writeBash` can (roughly) be implemented as:

    ```nix
    writeBash = makeScriptWriter { interpreter = "${pkgs.bash}/bin/bash"; }
    ```
    :::

    # Examples
    :::{.example}
    ## `pkgs.writers.makeScriptWriter` dash example

    ```nix-repl
    :b makeScriptWriter { interpreter = "${pkgs.dash}/bin/dash"; } "hello" "echo hello world"
    -> /nix/store/indvlr9ckmnv4f0ynkmasv2h4fxhand0-hello
    ```

    The above example creates a script named `hello` that outputs `hello world` when executed.

    ```sh
    > /nix/store/indvlr9ckmnv4f0ynkmasv2h4fxhand0-hello
    hello world
    ```
    :::

    :::{.example}
    ## `pkgs.writers.makeScriptWriter` python example

    ```nix-repl
    :b makeScriptWriter { interpreter = "${pkgs.python3}/bin/python"; } "python-hello" "print('hello world')"
    -> /nix/store/4kvby1hqr45ffcdrvfpnpj62hanskw93-python-hello
    ```

    ```sh
    > /nix/store/4kvby1hqr45ffcdrvfpnpj62hanskw93-python-hello
    hello world
    ```
    :::
  */
  makeScriptWriter =
    {
      interpreter,
      check ? "",
      makeWrapperArgs ? [ ],
    }:
    nameOrPath: content:
    assert
      (types.path.check nameOrPath)
      || (builtins.match "([0-9A-Za-z._])[0-9A-Za-z._-]*" nameOrPath != null);
    assert (types.path.check content) || (types.str.check content);
    let
      nameIsPath = types.path.check nameOrPath;
      name = last (builtins.split "/" nameOrPath);
      path = if nameIsPath then nameOrPath else "/bin/${name}";
      # The inner derivation which creates the executable under $out/bin (never at $out directly)
      # This is required in order to support wrapping, as wrapped programs consist of
      # at least two files: the executable and the wrapper.
      inner =
        pkgs.runCommandLocal name
          (
            {
              inherit makeWrapperArgs;
              nativeBuildInputs = [ makeBinaryWrapper ];
              meta.mainProgram = name;
            }
            // (
              if (types.str.check content) then
                {
                  inherit content interpreter;
                  passAsFile = [ "content" ];
                }
              else
                {
                  inherit interpreter;
                  contentPath = content;
                }
            )
          )
          ''
            # On darwin a script cannot be used as an interpreter in a shebang but
            # there doesn't seem to be a limit to the size of shebang and multiple
            # arguments to the interpreter are allowed.
            if [[ -n "${toString pkgs.stdenvNoCC.isDarwin}" ]] && isScript $interpreter
            then
              wrapperInterpreterLine=$(head -1 "$interpreter" | tail -c+3)
              # Get first word from the line (note: xargs echo remove leading spaces)
              wrapperInterpreter=$(echo "$wrapperInterpreterLine" | xargs echo | cut -d " " -f1)

              if isScript $wrapperInterpreter
              then
                echo "error: passed interpreter ($interpreter) is a script which has another script ($wrapperInterpreter) as an interpreter, which is not supported."
                exit 1
              fi

              # This should work as long as wrapperInterpreter is a shell, which is
              # the case for programs wrapped with makeWrapper, like
              # python3.withPackages etc.
              interpreterLine="$wrapperInterpreterLine $interpreter"
            else
              interpreterLine=$interpreter
            fi

            echo "#! $interpreterLine" > $out
            cat "$contentPath" >> $out
            ${optionalString (check != "") ''
              ${check} $out
            ''}
            chmod +x $out

            # Relocate executable
            # Wrap it if makeWrapperArgs are specified
            mv $out tmp
              mkdir -p $out/$(dirname "${path}")
              mv tmp $out/${path}
            if [ -n "''${makeWrapperArgs+''${makeWrapperArgs[@]}}" ]; then
                wrapProgram $out/${path} ''${makeWrapperArgs[@]}
            fi
          '';
    in
    if nameIsPath then
      inner
    # In case nameOrPath is a name, the user intends the executable to be located at $out.
    # This is achieved by creating a separate derivation containing a symlink at $out linking to ${inner}/bin/${name}.
    # This breaks the override pattern.
    # In case this turns out to be a problem, we can still add more magic
    else
      pkgs.runCommandLocal name { } ''
        ln -s ${inner}/bin/${name} $out
      '';

  /**
    `makeBinWriter` returns a derivation which compiles the given script into an executable format.

    :::{.note}
    This function is the base implementation for other compile language `writers`, such as `writeHaskell` and `writeRust`.
    :::

    # Inputs

    config (AttrSet)
    : `compileScript` (String)
      : The script that compiles the given content into an executable.

    : `strip` (Boolean, Default: true)
      : Whether to [strip](https://nixos.org/manual/nixpkgs/stable/#ssec-fixup-phase) the executable or not.

    : `makeWrapperArgs` (Optional, [ String ], Default: [])
      : Arguments forwarded to (`makeWrapper`)[#fun-makeWrapper]

    `nameOrPath` (String)
    : The name of the script or the path to the script.

      When a `string` starting with "/" is passed, the script will be created at the specified path in $out.
      For example, `"/bin/hello"` will create a script at `$out/bin/hello`.

      Any other `string` is interpreted as a filename.
      It must be a [POSIX filename](https://en.wikipedia.org/wiki/Filename) starting with a letter, digit, dot, or underscore.
      Spaces or special characters are not allowed.

    # Examples
    :::{.example}
    ## `pkgs.writers.makeBinWriter` example

    ```c
    // main.c
    #include <stdio.h>

    int main()
    {
        printf("Hello, World!\n");
        return 0;
    }
    ```

    ```nix-repl
    :b makeBinWriter { compileScript = "${pkgs.gcc}/bin/gcc -o $out $contentPath"; } "hello" ./main.c
    out -> /nix/store/f6crc8mwj3lvcxqclw7n09cm8nb6kxbh-hello
    ```

    The above example creates an executable named `hello` that outputs `Hello, World!` when executed.

    ```sh
    > /nix/store/f6crc8mwj3lvcxqclw7n09cm8nb6kxbh-hello
    Hello, World!
    ```
    :::
  */
  makeBinWriter =
    {
      compileScript,
      strip ? true,
      makeWrapperArgs ? [ ],
    }:
    nameOrPath: content:
    assert
      (types.path.check nameOrPath)
      || (builtins.match "([0-9A-Za-z._])[0-9A-Za-z._-]*" nameOrPath != null);
    assert (types.path.check content) || (types.str.check content);
    let
      nameIsPath = types.path.check nameOrPath;
      name = last (builtins.split "/" nameOrPath);
      path = if nameIsPath then nameOrPath else "/bin/${name}";
      # The inner derivation which creates the executable under $out/bin (never at $out directly)
      # This is required in order to support wrapping, as wrapped programs consist of at least two files: the executable and the wrapper.
      inner =
        pkgs.runCommandLocal name
          (
            {
              inherit makeWrapperArgs;
              nativeBuildInputs = [ makeBinaryWrapper ];
              meta.mainProgram = name;
            }
            // (
              if (types.str.check content) then
                {
                  inherit content;
                  passAsFile = [ "content" ];
                }
              else
                { contentPath = content; }
            )
          )
          ''
            ${compileScript}
            ${lib.optionalString strip "${lib.getBin buildPackages.bintools-unwrapped}/bin/${buildPackages.bintools-unwrapped.targetPrefix}strip -S $out"}
            # Sometimes binaries produced for darwin (e. g. by GHC) won't be valid
            # mach-o executables from the get-go, but need to be corrected somehow
            # which is done by fixupPhase.
            ${lib.optionalString pkgs.stdenvNoCC.hostPlatform.isDarwin "fixupPhase"}
            mv $out tmp
            mkdir -p $out/$(dirname "${path}")
            mv tmp $out/${path}
            if [ -n "''${makeWrapperArgs+''${makeWrapperArgs[@]}}" ]; then
              wrapProgram $out/${path} ''${makeWrapperArgs[@]}
            fi
          '';
    in
    if nameIsPath then
      inner
    # In case nameOrPath is a name, the user intends the executable to be located at $out.
    # This is achieved by creating a separate derivation containing a symlink at $out linking to ${inner}/bin/${name}.
    # This breaks the override pattern.
    # In case this turns out to be a problem, we can still add more magic
    else
      pkgs.runCommandLocal name { } ''
        ln -s ${inner}/bin/${name} $out
      '';

  # Like writeScript but the first line is a shebang to bash
  #
  # Can be called with or without extra arguments.
  #
  # Example without arguments:
  #   writeBash "example" ''
  #     echo hello world
  #   ''
  #
  # Example with arguments:
  #   writeBash "example"
  #     {
  #       makeWrapperArgs = [
  #         "--prefix" "PATH" ":" "${pkgs.hello}/bin"
  #       ];
  #     }
  #     ''
  #       hello
  #     ''
  writeBash =
    name: argsOrScript:
    if lib.isAttrs argsOrScript && !lib.isDerivation argsOrScript then
      makeScriptWriter (argsOrScript // { interpreter = "${lib.getExe pkgs.bash}"; }) name
    else
      makeScriptWriter { interpreter = "${lib.getExe pkgs.bash}"; } name argsOrScript;

  # Like writeScriptBin but the first line is a shebang to bash
  #
  # Can be called with or without extra arguments.
  #
  # Example without arguments:
  #   writeBashBin "example" ''
  #     echo hello world
  #   ''
  #
  # Example with arguments:
  #  writeBashBin "example"
  #    {
  #      makeWrapperArgs = [
  #        "--prefix", "PATH", ":", "${pkgs.hello}/bin",
  #      ];
  #    }
  #    ''
  #      hello
  #    ''
  writeBashBin = name: writeBash "/bin/${name}";

  # Like writeScript but the first line is a shebang to dash
  #
  # Can be called with or without extra arguments.
  #
  # Example without arguments:
  #   writeDash "example" ''
  #     echo hello world
  #   ''
  #
  # Example with arguments:
  #   writeDash "example"
  #     {
  #       makeWrapperArgs = [
  #         "--prefix", "PATH", ":", "${pkgs.hello}/bin",
  #       ];
  #     }
  #     ''
  #       hello
  #     ''
  writeDash =
    name: argsOrScript:
    if lib.isAttrs argsOrScript && !lib.isDerivation argsOrScript then
      makeScriptWriter (argsOrScript // { interpreter = "${lib.getExe pkgs.dash}"; }) name
    else
      makeScriptWriter { interpreter = "${lib.getExe pkgs.dash}"; } name argsOrScript;

  # Like writeScriptBin but the first line is a shebang to dash
  #
  # Can be called with or without extra arguments.
  #
  # Example without arguments:
  #   writeDashBin "example" ''
  #     echo hello world
  #   ''
  #
  # Example with arguments:
  #  writeDashBin "example"
  #    {
  #      makeWrapperArgs = [
  #        "--prefix", "PATH", ":", "${pkgs.hello}/bin",
  #      ];
  #    }
  #    ''
  #      hello
  #    ''
  writeDashBin = name: writeDash "/bin/${name}";

  # Like writeScript but the first line is a shebang to fish
  #
  # Can be called with or without extra arguments.
  #
  # Example without arguments:
  #   writeFish "example" ''
  #     echo hello world
  #   ''
  #
  # Example with arguments:
  #   writeFish "example"
  #     {
  #       makeWrapperArgs = [
  #         "--prefix", "PATH", ":", "${pkgs.hello}/bin",
  #       ];
  #     }
  #     ''
  #       hello
  #     ''
  writeFish =
    name: argsOrScript:
    if lib.isAttrs argsOrScript && !lib.isDerivation argsOrScript then
      makeScriptWriter (
        argsOrScript
        // {
          interpreter = "${lib.getExe pkgs.fish} --no-config";
          check = "${lib.getExe pkgs.fish} --no-config --no-execute"; # syntax check only
        }
      ) name
    else
      makeScriptWriter {
        interpreter = "${lib.getExe pkgs.fish} --no-config";
        check = "${lib.getExe pkgs.fish} --no-config --no-execute"; # syntax check only
      } name argsOrScript;

  # Like writeScriptBin but the first line is a shebang to fish
  #
  # Can be called with or without extra arguments.
  #
  # Example without arguments:
  #   writeFishBin "example" ''
  #     echo hello world
  #   ''
  #
  # Example with arguments:
  #   writeFishBin "example"
  #     {
  #       makeWrapperArgs = [
  #         "--prefix", "PATH", ":", "${pkgs.hello}/bin",
  #       ];
  #     }
  #     ''
  #       hello
  #     ''
  writeFishBin = name: writeFish "/bin/${name}";

  # writeHaskell takes a name, an attrset with libraries and haskell version (both optional)
  # and some haskell source code and returns an executable.
  #
  # Example:
  #   writeHaskell "missiles" { libraries = [ pkgs.haskellPackages.acme-missiles ]; } ''
  #     import Acme.Missiles
  #
  #     main = launchMissiles
  #   '';
  writeHaskell =
    name:
    {
      ghc ? pkgs.ghc,
      ghcArgs ? [ ],
      libraries ? [ ],
      makeWrapperArgs ? [ ],
      strip ? true,
      threadedRuntime ? true,
    }:
    let
      appendIfNotSet = el: list: if elem el list then list else list ++ [ el ];
      ghcArgs' = if threadedRuntime then appendIfNotSet "-threaded" ghcArgs else ghcArgs;

    in
    makeBinWriter {
      compileScript = ''
        cp $contentPath tmp.hs
        ${(ghc.withPackages (_: libraries))}/bin/ghc ${lib.escapeShellArgs ghcArgs'} tmp.hs
        mv tmp $out
      '';
      inherit makeWrapperArgs strip;
    } name;

  # writeHaskellBin takes the same arguments as writeHaskell but outputs a directory (like writeScriptBin)
  writeHaskellBin = name: writeHaskell "/bin/${name}";

  # Like writeScript but the first line is a shebang to nu
  #
  # Can be called with or without extra arguments.
  #
  # Example without arguments:
  #   writeNu "example" ''
  #     echo hello world
  #   ''
  #
  # Example with arguments:
  #   writeNu "example"
  #     {
  #       makeWrapperArgs = [
  #         "--prefix", "PATH", ":", "${pkgs.hello}/bin",
  #       ];
  #     }
  #     ''
  #       hello
  #     ''
  writeNu =
    name: argsOrScript:
    if lib.isAttrs argsOrScript && !lib.isDerivation argsOrScript then
      makeScriptWriter (
        argsOrScript // { interpreter = "${lib.getExe pkgs.nushell} --no-config-file"; }
      ) name
    else
      makeScriptWriter { interpreter = "${lib.getExe pkgs.nushell} --no-config-file"; } name argsOrScript;

  # Like writeScriptBin but the first line is a shebang to nu
  #
  # Can be called with or without extra arguments.
  #
  # Example without arguments:
  #   writeNuBin "example" ''
  #     echo hello world
  #   ''
  #
  # Example with arguments:
  #   writeNuBin "example"
  #     {
  #       makeWrapperArgs = [
  #         "--prefix", "PATH", ":", "${pkgs.hello}/bin",
  #       ];
  #     }
  #    ''
  #      hello
  #    ''
  writeNuBin = name: writeNu "/bin/${name}";

  # makeRubyWriter takes ruby and compatible rubyPackages and produces ruby script writer,
  # If any libraries are specified, ruby.withPackages is used as interpreter, otherwise the "bare" ruby is used.
  makeRubyWriter =
    ruby: rubyPackages: buildRubyPackages: name:
    {
      libraries ? [ ],
      ...
    }@args:
    makeScriptWriter (
      (builtins.removeAttrs args [ "libraries" ])
      // {
        interpreter =
          if libraries == [ ] then "${ruby}/bin/ruby" else "${(ruby.withPackages (ps: libraries))}/bin/ruby";
        # Rubocop doesn't seem to like running in this fashion.
        #check = (writeDash "rubocop.sh" ''
        #  exec ${lib.getExe buildRubyPackages.rubocop} "$1"
        #'');
      }
    ) name;

  # Like writeScript but the first line is a shebang to ruby
  #
  # Example:
  #   writeRuby "example" { libraries = [ pkgs.rubyPackages.git ]; } ''
  #    puts "hello world"
  #   ''
  writeRuby = makeRubyWriter pkgs.ruby pkgs.rubyPackages buildPackages.rubyPackages;

  writeRubyBin = name: writeRuby "/bin/${name}";

  # makeLuaWriter takes lua and compatible luaPackages and produces lua script writer,
  # which validates the script with luacheck at build time. If any libraries are specified,
  # lua.withPackages is used as interpreter, otherwise the "bare" lua is used.
  makeLuaWriter =
    lua: luaPackages: buildLuaPackages: name:
    {
      libraries ? [ ],
      ...
    }@args:
    makeScriptWriter (
      (builtins.removeAttrs args [ "libraries" ])
      // {
        interpreter = lua.interpreter;
        # if libraries == []
        # then lua.interpreter
        # else (lua.withPackages (ps: libraries)).interpreter
        # This should support packages! I just cant figure out why some dependency collision happens whenever I try to run this.
        check = (
          writeDash "luacheck.sh" ''
            exec ${buildLuaPackages.luacheck}/bin/luacheck "$1"
          ''
        );
      }
    ) name;

  # writeLua takes a name an attributeset with libraries and some lua source code and
  # returns an executable (should also work with luajit)
  #
  # Example:
  # writeLua "test_lua" { libraries = [ pkgs.luaPackages.say ]; } ''
  #   s = require("say")
  #   s:set_namespace("en")
  #
  #   s:set('money', 'I have %s dollars')
  #   s:set('wow', 'So much money!')
  #
  #   print(s('money', {1000})) -- I have 1000 dollars
  #
  #   s:set_namespace("fr") -- switch to french!
  #   s:set('wow', "Tant d'argent!")
  #
  #   print(s('wow')) -- Tant d'argent!
  #   s:set_namespace("en")  -- switch back to english!
  #   print(s('wow')) -- So much money!
  # ''
  writeLua = makeLuaWriter pkgs.lua pkgs.luaPackages buildPackages.luaPackages;

  writeLuaBin = name: writeLua "/bin/${name}";

  writeRust =
    name:
    {
      makeWrapperArgs ? [ ],
      rustc ? pkgs.rustc,
      rustcArgs ? [ ],
      strip ? true,
    }:
    let
      darwinArgs = lib.optionals stdenv.isDarwin [ "-L${lib.getLib libiconv}/lib" ];
    in
    makeBinWriter {
      compileScript = ''
        cp "$contentPath" tmp.rs
        PATH=${lib.makeBinPath [ pkgs.gcc ]} ${rustc}/bin/rustc ${lib.escapeShellArgs rustcArgs} ${lib.escapeShellArgs darwinArgs} -o "$out" tmp.rs
      '';
      inherit makeWrapperArgs strip;
    } name;

  writeRustBin = name: writeRust "/bin/${name}";

  # writeJS takes a name an attributeset with libraries and some JavaScript sourcecode and
  # returns an executable
  #
  # Example:
  #   writeJS "example" { libraries = [ pkgs.uglify-js ]; } ''
  #     var UglifyJS = require("uglify-js");
  #     var code = "function add(first, second) { return first + second; }";
  #     var result = UglifyJS.minify(code);
  #     console.log(result.code);
  #   ''
  writeJS =
    name:
    {
      libraries ? [ ],
    }:
    content:
    let
      node-env = pkgs.buildEnv {
        name = "node";
        paths = libraries;
        pathsToLink = [ "/lib/node_modules" ];
      };
    in
    writeDash name ''
      export NODE_PATH=${node-env}/lib/node_modules
      exec ${lib.getExe pkgs.nodejs} ${pkgs.writeText "js" content} "$@"
    '';

  # writeJSBin takes the same arguments as writeJS but outputs a directory (like writeScriptBin)
  writeJSBin = name: writeJS "/bin/${name}";

  awkFormatNginx = builtins.toFile "awkFormat-nginx.awk" ''
    awk -f
    {sub(/^[ \t]+/,"");idx=0}
    /\{/{ctx++;idx=1}
    /\}/{ctx--}
    {id="";for(i=idx;i<ctx;i++)id=sprintf("%s%s", id, "\t");printf "%s%s\n", id, $0}
  '';

  writeNginxConfig =
    name: text:
    pkgs.runCommandLocal name
      {
        inherit text;
        passAsFile = [ "text" ];
        nativeBuildInputs = [ gixy ];
      } # sh
      ''
        # nginx-config-formatter has an error - https://github.com/1connect/nginx-config-formatter/issues/16
        awk -f ${awkFormatNginx} "$textPath" | sed '/^\s*$/d' > $out
        gixy $out
      '';

  # writePerl takes a name an attributeset with libraries and some perl sourcecode and
  # returns an executable
  #
  # Example:
  #   writePerl "example" { libraries = [ pkgs.perlPackages.boolean ]; } ''
  #     use boolean;
  #     print "Howdy!\n" if true;
  #   ''
  writePerl =
    name:
    {
      libraries ? [ ],
      ...
    }@args:
    makeScriptWriter (
      (builtins.removeAttrs args [ "libraries" ])
      // {
        interpreter = "${lib.getExe (pkgs.perl.withPackages (p: libraries))}";
      }
    ) name;

  # writePerlBin takes the same arguments as writePerl but outputs a directory (like writeScriptBin)
  writePerlBin = name: writePerl "/bin/${name}";

  # makePythonWriter takes python and compatible pythonPackages and produces python script writer,
  # which validates the script with flake8 at build time. If any libraries are specified,
  # python.withPackages is used as interpreter, otherwise the "bare" python is used.
  makePythonWriter =
    python: pythonPackages: buildPythonPackages: name:
    {
      libraries ? [ ],
      flakeIgnore ? [ ],
      ...
    }@args:
    let
      ignoreAttribute =
        optionalString (flakeIgnore != [ ])
          "--ignore ${concatMapStringsSep "," escapeShellArg flakeIgnore}";
    in
    makeScriptWriter (
      (builtins.removeAttrs args [
        "libraries"
        "flakeIgnore"
      ])
      // {
        interpreter =
          if pythonPackages != pkgs.pypy2Packages || pythonPackages != pkgs.pypy3Packages then
            if libraries == [ ] then python.interpreter else (python.withPackages (ps: libraries)).interpreter
          else
            python.interpreter;
        check = optionalString python.isPy3k (
          writeDash "pythoncheck.sh" ''
            exec ${buildPythonPackages.flake8}/bin/flake8 --show-source ${ignoreAttribute} "$1"
          ''
        );
      }
    ) name;

  # writePyPy2 takes a name an attributeset with libraries and some pypy2 sourcecode and
  # returns an executable
  #
  # Example:
  # writePyPy2 "test_pypy2" { libraries = [ pkgs.pypy2Packages.enum ]; } ''
  #   from enum import Enum
  #
  #   class Test(Enum):
  #       a = "success"
  #
  #   print Test.a
  # ''
  writePyPy2 = makePythonWriter pkgs.pypy2 pkgs.pypy2Packages buildPackages.pypy2Packages;

  # writePyPy2Bin takes the same arguments as writePyPy2 but outputs a directory (like writeScriptBin)
  writePyPy2Bin = name: writePyPy2 "/bin/${name}";

  # writePython3 takes a name an attributeset with libraries and some python3 sourcecode and
  # returns an executable
  #
  # Example:
  # writePython3 "test_python3" { libraries = [ pkgs.python3Packages.pyyaml ]; } ''
  #   import yaml
  #
  #   y = yaml.safe_load("""
  #     - test: success
  #   """)
  #   print(y[0]['test'])
  # ''
  writePython3 = makePythonWriter pkgs.python3 pkgs.python3Packages buildPackages.python3Packages;

  # writePython3Bin takes the same arguments as writePython3 but outputs a directory (like writeScriptBin)
  writePython3Bin = name: writePython3 "/bin/${name}";

  # writePyPy3 takes a name an attributeset with libraries and some pypy3 sourcecode and
  # returns an executable
  #
  # Example:
  # writePyPy3 "test_pypy3" { libraries = [ pkgs.pypy3Packages.pyyaml ]; } ''
  #   import yaml
  #
  #   y = yaml.safe_load("""
  #     - test: success
  #   """)
  #   print(y[0]['test'])
  # ''
  writePyPy3 = makePythonWriter pkgs.pypy3 pkgs.pypy3Packages buildPackages.pypy3Packages;

  # writePyPy3Bin takes the same arguments as writePyPy3 but outputs a directory (like writeScriptBin)
  writePyPy3Bin = name: writePyPy3 "/bin/${name}";

  makeFSharpWriter =
    {
      dotnet-sdk ? pkgs.dotnet-sdk,
      fsi-flags ? "",
      libraries ? _: [ ],
      ...
    }@args:
    nameOrPath:
    let
      fname = last (builtins.split "/" nameOrPath);
      path = if strings.hasSuffix ".fsx" nameOrPath then nameOrPath else "${nameOrPath}.fsx";
      _nugetDeps = mkNugetDeps {
        name = "${fname}-nuget-deps";
        nugetDeps = libraries;
      };

      nuget-source = mkNugetSource {
        name = "${fname}-nuget-source";
        description = "Nuget source with the dependencies for ${fname}";
        deps = [ _nugetDeps ];
      };

      fsi = writeBash "fsi" ''
        export HOME=$NIX_BUILD_TOP/.home
        export DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1
        export DOTNET_CLI_TELEMETRY_OPTOUT=1
        export DOTNET_NOLOGO=1
        script="$1"; shift
        ${lib.getExe dotnet-sdk} fsi --quiet --nologo --readline- ${fsi-flags} "$@" < "$script"
      '';

    in
    content:
    makeScriptWriter
      (
        (builtins.removeAttrs args [
          "dotnet-sdk"
          "fsi-flags"
          "libraries"
        ])
        // {
          interpreter = fsi;
        }
      )
      path
      ''
        #i "nuget: ${nuget-source}/lib"
        ${content}
        exit 0
      '';

  writeFSharp = makeFSharpWriter { };

  writeFSharpBin = name: writeFSharp "/bin/${name}";
}