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diff --git a/nix/buildLisp/default.nix b/nix/buildLisp/default.nix
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+# buildLisp provides Nix functions to build Common Lisp packages,
+# targeting SBCL.
+#
+# buildLisp is designed to enforce conventions and do away with the
+# free-for-all of existing Lisp build systems.
+
+{ pkgs ? import <nixpkgs> {}, ... }:
+
+let
+  inherit (builtins) map elemAt match filter;
+  inherit (pkgs) lib runCommandNoCC makeWrapper writeText writeShellScriptBin sbcl;
+
+  #
+  # Internal helper definitions
+  #
+
+  # 'genLoadLisp' generates Lisp code that instructs SBCL to load all
+  # the provided Lisp libraries.
+  genLoadLisp = deps: lib.concatStringsSep "\n"
+    (map (lib: "(load \"${lib}/${lib.lispName}.fasl\")") (allDeps deps));
+
+  # 'genCompileLisp' generates a Lisp file that instructs SBCL to
+  # compile the provided list of Lisp source files to $out.
+  genCompileLisp = srcs: deps: writeText "compile.lisp" ''
+    ;; This file compiles the specified sources into the Nix build
+    ;; directory, creating one FASL file for each source.
+    (require 'sb-posix)
+
+    ${genLoadLisp deps}
+
+    (defun nix-compile-lisp (file srcfile)
+      (let ((outfile (make-pathname :type "fasl"
+                                    :directory (or (sb-posix:getenv "NIX_BUILD_TOP")
+                                                   (error "not running in a Nix build"))
+                                    :defaults srcfile)))
+        (multiple-value-bind (_outfile _warnings-p failure-p)
+            (compile-file srcfile :output-file outfile)
+          (if failure-p (sb-posix:exit 1)
+              (progn
+                ;; For the case of multiple files belonging to the same
+                ;; library being compiled, load them in order:
+                (load outfile)
+
+                ;; Write them to the FASL list in the same order:
+                (format file "cat ~a~%" (namestring outfile)))))))
+
+    (let ((*compile-verbose* t)
+          ;; FASL files are compiled into the working directory of the
+          ;; build and *then* moved to the correct out location.
+          (pwd (sb-posix:getcwd)))
+
+      (with-open-file (file "cat_fasls"
+                            :direction :output
+                            :if-does-not-exist :create)
+
+        ;; These forms were inserted by the Nix build:
+        ${
+          lib.concatStringsSep "\n" (map (src: "(nix-compile-lisp file \"${src}\")") srcs)
+        }
+        ))
+  '';
+
+  # 'dependsOn' determines whether Lisp library 'b' depends on 'a'.
+  dependsOn = a: b: builtins.elem a b.lispDeps;
+
+  # 'allDeps' flattens the list of dependencies (and their
+  # dependencies) into one ordered list of unique deps.
+  allDeps = deps: (lib.toposort dependsOn (lib.unique (
+    lib.flatten (deps ++ (map (d: d.lispDeps) deps))
+  ))).result;
+
+  # 'allNative' extracts all native dependencies of a dependency list
+  # to ensure that library load paths are set correctly during all
+  # compilations and program assembly.
+  allNative = native: deps: lib.unique (
+    lib.flatten (native ++ (map (d: d.lispNativeDeps) deps))
+  );
+
+  # 'genDumpLisp' generates a Lisp file that instructs SBCL to dump
+  # the currently loaded image as an executable to $out/bin/$name.
+  #
+  # TODO(tazjin): Compression is currently unsupported because the
+  # SBCL in nixpkgs is, by default, not compiled with zlib support.
+  genDumpLisp = name: main: deps: writeText "dump.lisp" ''
+    (require 'sb-posix)
+
+    ${genLoadLisp deps}
+
+    (let* ((bindir (concatenate 'string (sb-posix:getenv "out") "/bin"))
+           (outpath (make-pathname :name "${name}"
+                                   :directory bindir)))
+      (save-lisp-and-die outpath
+                         :executable t
+                         :toplevel (function ${main})
+                         :purify t))
+    ;;
+  '';
+
+  # Add an `overrideLisp` attribute to a function result that works
+  # similar to `overrideAttrs`, but is used specifically for the
+  # arguments passed to Lisp builders.
+  makeOverridable = f: orig: (f orig) // {
+    overrideLisp = new: makeOverridable f (orig // (new orig));
+  };
+
+  #
+  # Public API functions
+  #
+
+  # 'library' builds a list of Common Lisp files into a single FASL
+  # which can then be loaded into SBCL.
+  library = { name, srcs, deps ? [], native ? [] }:
+  let
+    lispNativeDeps = (allNative native deps);
+    lispDeps = allDeps deps;
+  in runCommandNoCC "${name}-cllib" {
+    LD_LIBRARY_PATH = lib.makeLibraryPath lispNativeDeps;
+    LANG = "C.UTF-8";
+  } ''
+    ${sbcl}/bin/sbcl --script ${genCompileLisp srcs lispDeps}
+
+    echo "Compilation finished, assembling FASL files"
+
+    # FASL files can be combined by simply concatenating them
+    # together, but it needs to be in the compilation order.
+    mkdir $out
+
+    chmod +x cat_fasls
+    ./cat_fasls > $out/${name}.fasl
+  '' // {
+    inherit lispNativeDeps lispDeps;
+    lispName = name;
+    lispBinary = false;
+  };
+
+  # 'program' creates an executable containing a dumped image of the
+  # specified sources and dependencies.
+  program = { name, main ? "${name}:main", srcs, deps ? [], native ? [] }:
+  let
+    lispDeps = allDeps deps;
+    libPath = lib.makeLibraryPath (allNative native lispDeps);
+    selfLib = library {
+      inherit name srcs native;
+      deps = lispDeps;
+    };
+  in runCommandNoCC "${name}" {
+    nativeBuildInputs = [ makeWrapper ];
+    LD_LIBRARY_PATH = libPath;
+  } ''
+    mkdir -p $out/bin
+
+    ${sbcl}/bin/sbcl --script ${
+      genDumpLisp name main ([ selfLib ] ++ lispDeps)
+    }
+
+    wrapProgram $out/bin/${name} --prefix LD_LIBRARY_PATH : "${libPath}"
+  '' // {
+    lispName = name;
+    lispDeps = [ selfLib ];
+    lispNativeDeps = native;
+    lispBinary = true;
+  };
+
+  # 'bundled' creates a "library" that calls 'require' on a built-in
+  # package, such as any of SBCL's sb-* packages.
+  bundled = name: (makeOverridable library) {
+    inherit name;
+    srcs = lib.singleton (builtins.toFile "${name}.lisp" "(require '${name})");
+  };
+
+  # 'sbclWith' creates an image with the specified libraries /
+  # programs loaded.
+  sbclWith = deps:
+  let lispDeps = filter (d: !d.lispBinary) (allDeps deps);
+  in writeShellScriptBin "sbcl" ''
+    export LD_LIBRARY_PATH=${lib.makeLibraryPath (allNative [] lispDeps)};
+    exec ${sbcl}/bin/sbcl ${lib.optionalString (deps != []) "--load ${writeText "load.lisp" (genLoadLisp lispDeps)}"} $@
+  '';
+in {
+  library = makeOverridable library;
+  program = makeOverridable program;
+  sbclWith = makeOverridable sbclWith;
+  bundled = makeOverridable bundled;
+}