feat(deps): add support for Nix package manager (#116)

This serves as an alternative to Homebrew. It should be much more stable
and cause less headaches over time for automated builds.

There should be no change to the end user experience of using the build
script, as it should still work with and use Homebrew by default.

Additionally, Nix provides older Apple SDKs, allowing us to run against
macOS 11.x SDKs. This allows the resulting Emacs.app builds to be
compatible with macOS 11.x and later versions.

In testing, this seems to be the case on macOS 11.x (x86_64) and macOS
12.x (arm64).

.github/workflows/ci.yml

@@ -8,13 +8,13 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-go@v4
+      - uses: actions/setup-go@v5
         with:
-          go-version: "1.20"
+          go-version: "1.23"
       - name: golangci-lint
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v6
         with:
-          version: v1.55
+          version: v1.61
         env:
           VERBOSE: "true"
 
@@ -23,9 +23,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-go@v4
+      - uses: actions/setup-go@v5
         with:
-          go-version: "1.20"
+          go-version: "1.23"
       - name: Check if mods are tidy
         run: make check-tidy
 
@@ -34,9 +34,9 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-go@v4
+      - uses: actions/setup-go@v5
         with:
-          go-version: "1.20"
+          go-version: "1.23"
       - name: Run tests
         run: make test
         env:

.gitignore

@@ -1,7 +1,6 @@
 .DS_Store
 .envrc
 Formula/*
-Gemfile.lock
 bin
 builds
 sources

.golangci.yml

@@ -7,7 +7,6 @@ linters-settings:
   gocyclo:
     min-complexity: 20
   govet:
-    check-shadowing: true
     enable-all: true
     disable:
       - fieldalignment
@@ -23,9 +22,9 @@ linters:
   disable-all: true
   enable:
     - bodyclose
+    - copyloopvar
     - dupl
     - errcheck
-    - exportloopref
     - funlen
     - gochecknoinits
     - goconst
@@ -72,12 +71,12 @@ issues:
     - source: "`yaml:"
       linters:
         - lll
-
+  exclude-dirs:
-run:
-  skip-dirs:
     - builds
     - sources
     - tarballs
+
+run:
   timeout: 2m
   allow-parallel-runners: true
   modules-download-mode: readonly

Gemfile

@@ -5,8 +5,5 @@ source 'http://rubygems.org/'
 gem 'ruby-macho'
 
 group :development do
-  gem 'byebug'
   gem 'rubocop'
-  gem 'rubocop-daemon'
-  gem 'solargraph', '~> 0.39.17'
 end

Gemfile.lock

@@ -0,0 +1,40 @@
+GEM
+  remote: http://rubygems.org/
+  specs:
+    ast (2.4.2)
+    json (2.8.2)
+    language_server-protocol (3.17.0.3)
+    parallel (1.26.3)
+    parser (3.3.6.0)
+      ast (~> 2.4.1)
+      racc
+    racc (1.8.1)
+    rainbow (3.1.1)
+    regexp_parser (2.9.2)
+    rubocop (1.68.0)
+      json (~> 2.3)
+      language_server-protocol (>= 3.17.0)
+      parallel (~> 1.10)
+      parser (>= 3.3.0.2)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 2.4, < 3.0)
+      rubocop-ast (>= 1.32.2, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.36.1)
+      parser (>= 3.3.1.0)
+    ruby-macho (4.1.0)
+    ruby-progressbar (1.13.0)
+    unicode-display_width (2.6.0)
+
+PLATFORMS
+  arm64-darwin
+  ruby
+  x86_64-darwin
+
+DEPENDENCIES
+  rubocop
+  ruby-macho
+
+BUNDLED WITH
+   2.5.23

Makefile

@@ -48,10 +48,12 @@ SHELL := env \
 bootstrap: bootstrap-brew bootstrap-ruby
 
 bootstrap-ruby:
-	bundle install
+	env BUNDLE_WITHOUT=development bundle install
 
 bootstrap-brew:
+ifndef IN_NIX_SHELL
 	brew bundle --verbose
+endif
 
 bootstrap-pip:
 	$(PIP) install -r requirements-ci.txt
@@ -69,7 +71,7 @@ $(TOOLDIR)/$(1): Makefile
 endef
 
 $(eval $(call tool,gofumpt,mvdan.cc/gofumpt@latest))
-$(eval $(call tool,golangci-lint,github.com/golangci/golangci-lint/cmd/golangci-lint@v1.55))
+$(eval $(call tool,golangci-lint,github.com/golangci/golangci-lint/cmd/golangci-lint@v1.61))
 $(eval $(call tool,gomod,github.com/Helcaraxan/gomod@latest))
 
 .PHONY: tools
@@ -132,6 +134,21 @@ format: $(TOOLDIR)/gofumpt
 gen:
 	go generate $$(go list ./... | grep -v 'sources/' | grep -v 'builds/')
 
+.PHONY: nix-flake-update
+nix-flake-update:
+	nix flake update \
+	&& $(MAKE) flake-package-versions.txt
+
+.SILENT: flake-package-versions
+flake-package-versions:
+	nix develop --command -- bash -c \
+		'nix derivation show \
+			$$(echo $$PATH | tr ":" "\n" | grep "/nix/store" | sort -u) \
+			| jq -r ".[].name" | sort -u'
+
+flake-package-versions.txt: flake.nix flake.lock
+	$(MAKE) flake-package-versions > flake-package-versions.txt
+
 #
 # Dependencies
 #

README.md

@@ -36,18 +36,40 @@ The build produced does have some limitations:
 
 ## Requirements
 
+Required with both Nix and Homebrew approaches:
+
 - [Xcode](https://apps.apple.com/gb/app/xcode/id497799835?mt=12)
-- [Homebrew](https://brew.sh/)
+
-- Ruby 2.3.0 or later is needed to execute the build script itself. macOS comes
+### Nix
-  with Ruby, check your version with `ruby --version`. If it's too old, you can
+
-  install a newer version with:
+The [Nix](https://nixos.org/) package manager is the preferred and most reliable
-  ```
+way to install all dependencies required to build Emacs, by way of a Nix flake
-  brew install ruby
+included in the project root.
-  ```
+
-- All dependencies can all easily be installed by running:
+To install all required dependencies within the nix shell, run:
-  ```
+
-  make bootstrap
+```
-  ```
+nix develop --command make bootstrap
+```
+
+### Homebrew
+
+If you do not have Nix installed, then the alternative way to manage and install
+build-time dependencies is via [Homebrew](https://brew.sh/).
+
+Ruby 3.3.x or later is also needed to execute the build script. Earlier versions
+may work, but are untested. Simplest way to install a recent Ruby version is via
+Homebrew:
+
+```
+brew install ruby
+```
+
+And finally, to install all built-time dependencies, run:
+
+```
+make bootstrap
+```
 
 ## Status
 
@@ -71,6 +93,24 @@ Nightly builds are built with GitHub Actions on GitHub-hosted runners, using
 
 ## Usage
 
+### Nix
+
+Ensure [Flakes](https://nixos.wiki/wiki/Flakes) are enabled, and enter the flake
+development environment with `nix develop`. Within this environment, you can
+execute the `./build-emacs-for-macos --help` to get started.
+
+Or you can run the build script via `nix develop`:
+
+```
+nix develop --command ./build-emacs-for-macos --help
+```
+
+### Homebrew
+
+Run `make boostrap` to ensure all Ruby and Homebrew dependencies are installed.
+
+### Build Script
+
 ```
 Usage: ./build-emacs-for-macos [options] <branch/tag/sha>
 
@@ -78,8 +118,11 @@ Branch, tag, and SHA are from the emacs-mirror/emacs/emacs Github repo,
 available here: https://github.com/emacs-mirror/emacs
 
 Options:
+        --info                       Print environment info and detected library paths, then exit
+        --preview                    Print preview details about build and exit.
     -j, --parallel COUNT             Compile using COUNT parallel processes (detected: 16)
         --git-sha SHA                Override detected git SHA of specified branch allowing builds of old commits
+        --[no-]use-nix               Use Nix instead of Homebrew to find dependencies (default: enabled if IN_NIX_SHELL is set)
         --[no-]xwidgets              Enable/disable XWidgets if supported (default: enabled)
         --[no-]tree-sitter           Enable/disable tree-sitter if supported (default: enabled)
         --[no-]native-comp           Enable/disable native-comp (default: enabled if supported)

build-emacs-for-macos

@@ -96,17 +96,26 @@ class OS
     @version ||= OSVersion.new
   end
 
+  def self.sdk_version
+    @sdk_version ||= SDKVersion.new
+  end
+
   def self.arch
     @arch ||= `uname -m`.strip
   end
 end
 
-class OSVersion
+class AbstractVersion
+  attr_reader :version
+
   def initialize
-    @version =
+    @version = load_version.match(
-      `sw_vers -productVersion`.match(
+      /(?<major>\d+)(?:\.(?<minor>\d+)(?:\.(?<patch>\d+))?)?/
-        /(?<major>\d+)(?:\.(?<minor>\d+)(?:\.(?<patch>\d+))?)?/
+    )
-      )
+  end
+
+  def load_version
+    raise NotImplementedError
   end
 
   def to_s
@@ -126,6 +135,21 @@ class OSVersion
   end
 end
 
+class OSVersion < AbstractVersion
+  def load_version
+    `sw_vers -productVersion`.strip
+  end
+end
+
+class SDKVersion < AbstractVersion
+  def load_version
+    ENV.fetch(
+      'MACOSX_DEPLOYMENT_TARGET',
+      `xcrun --show-sdk-version 2>/dev/null`.strip
+    ).strip
+  end
+end
+
 class Build
   include Output
   include System
@@ -142,12 +166,12 @@ class Build
     @root_dir = root_dir
     @ref = ref || 'master'
     @options = options
-    @gcc_info = GccInfo.new
+    @gcc_info = GccInfo.new(use_nix: options[:use_nix])
+
+    load_plan(options[:plan]) if options[:plan]
   end
 
   def build
-    load_plan(options[:plan]) if options[:plan]
-
     unless meta[:sha] && meta[:date]
       fatal 'Failed to get commit info from GitHub.'
     end
@@ -167,7 +191,7 @@ class Build
     CSourcesEmbedder.new(app, @source_dir).embed
     LibEmbedder.new(
       app,
-      brew_dir,
+      [brew_dir, '/nix/store'],
       extra_libs,
       relink_eln_files: options[:relink_eln]
     ).embed
@@ -177,6 +201,61 @@ class Build
     archive_build(build_dir) if options[:archive]
   end
 
+  def print_info
+    # Force-enable native-comp to ensure all env vars are setup.
+    options[:native_comp] = true
+
+    puts YAML.dump(
+      {
+        'os' => OS.version.to_s,
+        'sdk' => OS.sdk_version.to_s,
+        'arch' => OS.arch,
+        'gcc' => {
+          'root' => gcc_info.root_dir,
+          'lib' => gcc_info.lib_dir,
+          'darwin_lib' => gcc_info.darwin_lib_dir,
+          'target_lib' => gcc_info.target_lib_dir,
+          'target_darwin_lib' => gcc_info.target_darwin_lib_dir,
+          'sanitized_target_darwin_lib_dir' =>
+          gcc_info.sanitized_target_darwin_lib_dir,
+          'version' => gcc_info.major_version
+        },
+        'libgccjit' => {
+          'root' => gcc_info.libgccjit_root_dir,
+          'lib' => gcc_info.libgccjit_lib_dir,
+          'version' => gcc_info.libgccjit_major_version
+        },
+        'env' => {
+          'CC' => compile_env['CC'],
+          'CFLAGS' => compile_env['CFLAGS']&.split,
+          'LDFLAGS' => compile_env['LDFLAGS']&.split,
+          'LIBRARY_PATH' => compile_env['LIBRARY_PATH']&.split(':'),
+          'PKG_CONFIG_PATH' => compile_env['PKG_CONFIG_PATH']&.split(':'),
+          'PATH' => compile_env['PATH']&.split(':')
+        }
+      }
+    )
+  end
+
+  def print_preview
+    puts YAML.dump(
+      {
+        'build_name' => build_name,
+        'emacs' => {
+          'ref' => meta[:ref],
+          'sha' => meta[:sha],
+          'date' => meta[:date]
+        },
+        'os_version' => OS.version.to_s,
+        'sdk_version' => OS.sdk_version.to_s,
+        'arch' => OS.arch,
+        'native_comp' => options[:native_comp],
+        'gcc_version' => gcc_info.major_version,
+        'libgccjit_version' => gcc_info.libgccjit_major_version
+      }
+    )
+  end
+
   private
 
   def load_plan(filename)
@@ -217,11 +296,16 @@ class Build
     @github_src_repo ||= options[:github_src_repo] || DEFAULT_GITHUB_REPO
   end
 
+  def use_nix?
+    !!options[:use_nix]
+  end
+
   def brew_dir
     @brew_dir ||= `brew --prefix`.chomp
   end
 
   def extra_libs
+    return [] if use_nix?
     return @extra_libs if @extra_libs
 
     libs = [
@@ -359,6 +443,11 @@ class Build
 
   def autogen
     FileUtils.cd(source_dir) do
+      if File.exist?('configure')
+        info 'configure script exists, skipping autogen.'
+        return
+      end
+
       if File.exist?('autogen/copy_autogen')
         run_cmd 'autogen/copy_autogen'
       elsif File.exist?('autogen.sh')
@@ -367,6 +456,135 @@ class Build
     end
   end
 
+  # rubocop:disable Naming/MethodName,Naming/VariableName
+  def env_CFLAGS
+    return @env_CFLAGS if @env_CFLAGS
+
+    env = []
+
+    env << '-O2'
+
+    if options[:native_comp]
+      env += [
+        "-I#{File.join(gcc_info.root_dir, 'include')}",
+        "-I#{File.join(gcc_info.libgccjit_root_dir, 'include')}"
+      ]
+    end
+
+    env << '-march=native' if options[:native_march]
+
+    if options[:fd_setsize].respond_to?(:>=) && options[:fd_setsize] >= 1024
+      env += [
+        "-DFD_SETSIZE=#{options[:fd_setsize]}",
+        '-DDARWIN_UNLIMITED_SELECT'
+      ]
+    end
+
+    if use_nix? && ENV['NIX_CFLAGS_COMPILE']
+      env += ENV['NIX_CFLAGS_COMPILE'].split
+    end
+
+    @env_CFLAGS = env
+  end
+
+  def env_LDFLAGS
+    return @env_LDFLAGS if @env_LDFLAGS
+
+    env = []
+
+    # Ensure library re-linking and code signing will work after building.
+    env << '-Wl,-headerpad_max_install_names'
+
+    if options[:native_comp]
+      env += [
+        "-L#{gcc_info.lib_dir}",
+        "-L#{gcc_info.darwin_lib_dir}",
+        "-L#{gcc_info.libgccjit_lib_dir}",
+        "-I#{File.join(gcc_info.root_dir, 'include')}",
+        "-I#{File.join(gcc_info.libgccjit_root_dir, 'include')}"
+      ]
+    end
+
+    env += ENV['NIX_LDFLAGS'].split if use_nix? && ENV['NIX_LDFLAGS']
+
+    @env_LDFLAGS = env
+  end
+
+  def env_LIBRARY_PATH
+    return @env_LIBRARY_PATH if @env_LIBRARY_PATH
+
+    env = []
+
+    if options[:native_comp]
+      env += [
+        gcc_info.lib_dir,
+        gcc_info.darwin_lib_dir,
+        gcc_info.libgccjit_lib_dir
+      ]
+    end
+
+    env << '/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib'
+
+    @env_LIBRARY_PATH = env
+  end
+
+  def env_PKG_CONFIG_PATH
+    return [] if use_nix?
+
+    @env_PKG_CONFIG_PATH ||= [
+      File.join(brew_dir, 'lib/pkgconfig'),
+      File.join(brew_dir, 'share/pkgconfig'),
+      File.join(brew_dir, 'opt/expat/lib/pkgconfig'),
+      File.join(brew_dir, 'opt/libxml2/lib/pkgconfig'),
+      File.join(brew_dir, 'opt/ncurses/lib/pkgconfig'),
+      File.join(brew_dir, 'opt/zlib/lib/pkgconfig'),
+      File.join(
+        brew_dir,
+        'Homebrew/Library/Homebrew/os/mac/pkgconfig',
+        OS.version.to_s
+      )
+    ]
+  end
+
+  def env_PATH
+    return [] if use_nix?
+
+    @env_PATH ||= [
+      File.join(brew_dir, 'opt/make/libexec/gnubin'),
+      File.join(brew_dir, 'opt/coreutils/libexec/gnubin'),
+      File.join(brew_dir, 'opt/gnu-sed/libexec/gnubin'),
+      File.join(brew_dir, 'bin'),
+      File.join(brew_dir, 'opt/texinfo/bin')
+    ]
+  end
+  # rubocop:enable Naming/MethodName,Naming/VariableName
+
+  def compile_env
+    return @compile_env if @compile_env
+
+    env = {
+      'CC' => use_nix? ? 'clang' : '/usr/bin/clang',
+      'PATH' => [
+        env_PATH, ENV.fetch('PATH', nil)
+      ].flatten.compact.reject(&:empty?).join(':'),
+      'PKG_CONFIG_PATH' => [
+        env_PKG_CONFIG_PATH,
+        ENV.fetch('PKG_CONFIG_PATH', nil)
+      ].flatten.compact.reject(&:empty?).join(':')
+    }
+
+    if options[:native_comp]
+      env['CFLAGS'] = [env_CFLAGS, ENV.fetch('CFLAGS', nil)]
+                      .flatten.compact.reject(&:empty?).join(' ')
+      env['LDFLAGS'] = [env_LDFLAGS, ENV.fetch('LDFLAGS', nil)]
+                       .flatten.compact.reject(&:empty?).join(' ')
+      env['LIBRARY_PATH'] = [env_LIBRARY_PATH, ENV.fetch('LIBRARY_PATH', nil)]
+                            .flatten.compact.reject(&:empty?).join(':')
+    end
+
+    @compile_env = env
+  end
+
   def compile_source(source)
     target = File.join(source, 'nextstep')
     emacs_app = File.join(target, 'Emacs.app')
@@ -384,71 +602,9 @@ class Build
         info 'Compiling with native-comp enabled'
         verify_native_comp
         gcc_info.verify_libgccjit
-
-        ENV['CFLAGS'] = [
-          "-I#{File.join(gcc_info.root_dir, 'include')}",
-          "-I#{File.join(gcc_info.libgccjit_root_dir, 'include')}",
-          '-O2',
-          (options[:native_march] ? '-march=native' : nil),
-          ENV.fetch('CFLAGS', nil)
-        ].compact.join(' ')
-
-        ENV['LDFLAGS'] = [
-          "-L#{gcc_info.lib_dir}",
-          "-L#{gcc_info.darwin_lib_dir}",
-          "-L#{gcc_info.libgccjit_lib_dir}",
-          "-I#{File.join(gcc_info.root_dir, 'include')}",
-          "-I#{File.join(gcc_info.libgccjit_root_dir, 'include')}",
-          # Ensure library re-linking and code signing will work after building.
-          '-Wl,-headerpad_max_install_names',
-          ENV.fetch('LDFLAGS', nil)
-        ].compact.join(' ')
-
-        ENV['LIBRARY_PATH'] = [
-          gcc_info.lib_dir,
-          gcc_info.darwin_lib_dir,
-          gcc_info.libgccjit_lib_dir,
-          ENV.fetch('LIBRARY_PATH', nil)
-        ].compact.join(':')
       end
 
-      if options[:fd_setsize].respond_to?(:>=) && options[:fd_setsize] >= 1024
+      compile_env.each { |k, v| ENV[k] = v }
-        ENV['CFLAGS'] = [
-          "-DFD_SETSIZE=#{options[:fd_setsize]}",
-          '-DDARWIN_UNLIMITED_SELECT',
-          ENV.fetch('CFLAGS', nil)
-        ].compact.join(' ')
-      end
-
-      ENV['CC'] = 'clang'
-      ENV['PKG_CONFIG_PATH'] = [
-        File.join(brew_dir, 'lib/pkgconfig'),
-        File.join(brew_dir, 'share/pkgconfig'),
-        File.join(brew_dir, 'opt/expat/lib/pkgconfig'),
-        File.join(brew_dir, 'opt/libxml2/lib/pkgconfig'),
-        File.join(brew_dir, 'opt/ncurses/lib/pkgconfig'),
-        File.join(brew_dir, 'opt/zlib/lib/pkgconfig'),
-        File.join(
-          brew_dir,
-          'Homebrew/Library/Homebrew/os/mac/pkgconfig',
-          OS.version.to_s
-        ),
-        ENV.fetch('PKG_CONFIG_PATH', nil)
-      ].compact.join(':')
-
-      ENV['PATH'] = [
-        File.join(brew_dir, 'opt/make/libexec/gnubin'),
-        File.join(brew_dir, 'opt/coreutils/libexec/gnubin'),
-        File.join(brew_dir, 'opt/gnu-sed/libexec/gnubin'),
-        File.join(brew_dir, 'bin'),
-        File.join(brew_dir, 'opt/texinfo/bin'),
-        ENV.fetch('PATH', nil)
-      ].compact.join(':')
-
-      ENV['LIBRARY_PATH'] = [
-        ENV.fetch('LIBRARY_PATH', nil),
-        '/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib'
-      ].compact.join(':')
 
       local_lisp_path = [
         ENV.fetch('EMACS_LOCAL_LISP_PATH', '').split(':'),
@@ -477,7 +633,7 @@ class Build
 
       # Disable aligned_alloc on Mojave and below. See issue:
       # https://github.com/daviderestivo/homebrew-emacs-head/issues/15
-      if OS.version.major <= 10 && OS.version.minor <= 14
+      if OS.sdk_version.major <= 10 && OS.sdk_version.minor <= 14
         info 'Force disabling of aligned_alloc on macOS Mojave (10.14.x) ' \
              'and earlier'
         disable_alligned_alloc
@@ -649,7 +805,7 @@ class Build
         meta[:date]&.strftime('%Y-%m-%d'),
         meta[:sha][0..6],
         meta[:ref],
-        "macOS-#{OS.version}",
+        "macOS-#{OS.sdk_version}",
         OS.arch
       ].compact.map { |v| v.gsub(/[^\w_-]+/, '-') }
 
@@ -972,6 +1128,16 @@ class AbstractEmbedder
   def resources_dir
     @resources_dir ||= File.join(app, 'Contents', 'Resources')
   end
+
+  private
+
+  def while_writable(file)
+    mode = File.stat(file).mode
+    File.chmod(0o775, file)
+    yield
+  ensure
+    File.chmod(mode, file) if File.exist?(file)
+  end
 end
 
 class CLIHelperEmbedder < AbstractEmbedder
@@ -1036,14 +1202,14 @@ class CSourcesEmbedder < AbstractEmbedder
 end
 
 class LibEmbedder < AbstractEmbedder
-  attr_reader :lib_source
+  attr_reader :lib_sources
   attr_reader :extra_libs
   attr_reader :relink_eln_files
 
-  def initialize(app, lib_source, extra_libs = [], relink_eln_files: true)
+  def initialize(app, sources = [], extra_libs = [], relink_eln_files: true)
     super(app)
 
-    @lib_source = lib_source
+    @lib_sources = sources
     @extra_libs = extra_libs
     @relink_eln_files = relink_eln_files
   end
@@ -1167,9 +1333,9 @@ class LibEmbedder < AbstractEmbedder
 
       debug "-- -- Resolved to: #{lib_filepath}" if linked_dylib != lib_filepath
 
-      # Only bundle libraries from lib_source.
+      # Only bundle libraries from lib_sources.
-      unless lib_filepath.start_with?(lib_source)
+      unless lib_sources.any? { |p| lib_filepath.start_with?(p) }
-        debug "-- -- Skipping, not from lib_source: #{lib_source}"
+        debug "-- -- Skipping, not from lib_sources: #{lib_sources.join(', ')}"
         next
       end
 
@@ -1219,7 +1385,15 @@ class LibEmbedder < AbstractEmbedder
       next if dylib_id.nil? || dylib_id == ''
 
       while_writable(target) do
-        MachO::Tools.change_dylib_id(target, dylib_id)
+        file = MachO.open(target)
+        file.change_dylib_id(dylib_id)
+
+        # Remove all rpaths except for @loader_path. Any other rpaths present in
+        # embedded libraries will potentially cause issues.
+        rpaths = file.rpaths.reject { |r| r == '@loader_path' }
+        rpaths.each { |r| file.delete_rpath(r) }
+
+        file.write!
       end
     end
 
@@ -1245,14 +1419,6 @@ class LibEmbedder < AbstractEmbedder
       while_writable(target_file) { mf.write! } if changed
     end
   end
-
-  def while_writable(file)
-    mode = File.stat(file).mode
-    File.chmod(0o775, file)
-    yield
-  ensure
-    File.chmod(mode, file) if File.exist?(file)
-  end
 end
 
 class GccLibEmbedder < AbstractEmbedder
@@ -1275,12 +1441,31 @@ class GccLibEmbedder < AbstractEmbedder
       fatal "No suitable GCC lib dir found in #{gcc_info.root_dir}"
     end
 
-    FileUtils.mkdir_p(File.dirname(target_dir))
+    FileUtils.mkdir_p(target_dir)
-    run_cmd('cp', '-pRL', source_dir, target_dir)
+    run_cmd(
-    FileUtils.rm(Dir[File.join(target_dir, '**', '.DS_Store')], force: true)
+      'rsync', '-rlptD',
+      # Exclude lib symlink which points at itself when using nix.
+      '--exclude', 'lib',
+      # Exclude gcc directory which holds apple-darwin libs, we copy those
+      # separately.
+      '--exclude', 'gcc',
+      File.join(source_dir, ''), target_dir
+    )
     run_cmd('chmod', '-R', 'u+w', target_dir)
-    if source_darwin_dir != target_darwin_dir
+    tidy_lib_rpaths(target_dir)
-      run_cmd('mv', source_darwin_dir, target_darwin_dir)
+
+    FileUtils.mkdir_p(target_darwin_dir)
+    run_cmd(
+      'rsync', '-rlptD',
+      File.join(source_darwin_dir, ''), target_darwin_dir
+    )
+    run_cmd('chmod', '-R', 'u+w', target_darwin_dir)
+    tidy_lib_rpaths(target_darwin_dir)
+
+    FileUtils.rm(Dir[File.join(target_dir, '**', '.DS_Store')], force: true)
+
+    if target_darwin_dir != sanitized_target_darwin_dir
+      run_cmd('mv', target_darwin_dir, sanitized_target_darwin_dir)
     end
 
     env_setup = ERB.new(NATIVE_COMP_ENV_VAR_TPL).result(gcc_info.get_binding)
@@ -1305,10 +1490,10 @@ class GccLibEmbedder < AbstractEmbedder
              (devtools-dir
               "/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib")
              (gcc-dir (expand-file-name
-                       "<%= app_bundle_relative_lib_dir %>"
+                       "<%= app_bundle_target_lib_dir %>"
                        invocation-directory))
              (darwin-dir (expand-file-name
-                          "<%= app_bundle_relative_darwin_lib_dir %>"
+                          "<%= app_bundle_target_darwin_lib_dir %>"
                           invocation-directory))
              (lib-paths (list)))
 
@@ -1322,26 +1507,50 @@ class GccLibEmbedder < AbstractEmbedder
         (setenv "LIBRARY_PATH" (mapconcat 'identity lib-paths ":"))))
   ELISP
 
+  # Remove all rpaths from Mach-O library files except for @loader_path.
+  def tidy_lib_rpaths(directory)
+    Dir[File.join(directory, '**', '*.{dylib,so}')].each do |file_path|
+      next if File.symlink?(file_path)
+
+      begin
+        mf = MachO.open(file_path)
+      rescue MachO::NotAMachOError
+        next
+      end
+
+      rpaths = mf.rpaths.reject { |r| r == '@loader_path' }
+      next if rpaths.none?
+
+      debug "Tidying up rpaths from: #{relative_path(file_path)}"
+      rpaths.each { |r| mf.delete_rpath(r) }
+      mf.write!
+    end
+  end
+
   def embedded?
     Dir[File.join(target_dir, 'libgcc*')].any?
   end
 
   def target_dir
-    File.join(lib_dir, gcc_info.relative_lib_dir)
+    File.join(lib_dir, gcc_info.target_lib_dir)
-  end
-
-  def source_darwin_dir
-    File.join(lib_dir, gcc_info.relative_darwin_lib_dir)
   end
 
   def target_darwin_dir
-    File.join(lib_dir, gcc_info.sanitized_relative_darwin_lib_dir)
+    File.join(lib_dir, gcc_info.target_darwin_lib_dir)
+  end
+
+  def sanitized_target_darwin_dir
+    File.join(lib_dir, gcc_info.sanitized_target_darwin_lib_dir)
   end
 
   def source_dir
     gcc_info.lib_dir
   end
 
+  def source_darwin_dir
+    gcc_info.darwin_lib_dir
+  end
+
   def relative_dir(path, root)
     Pathname.new(path).relative_path_from(Pathname.new(root)).to_s
   end
@@ -1354,86 +1563,132 @@ end
 class GccInfo
   include Output
 
+  def initialize(use_nix: false)
+    @use_nix = use_nix
+  end
+
+  def use_nix?
+    @use_nix
+  end
+
   def root_dir
-    @root_dir ||= `brew --prefix gcc`.chomp
+    @root_dir ||=
+      if use_nix?
+        libgccjit_root_dir
+      else
+        `brew --prefix gcc`.chomp
+      end
   end
 
   def major_version
-    @major_version ||= File.basename(lib_dir)
+    @major_version ||=
+      if use_nix?
+        libgccjit_major_version
+      else
+        File.basename(lib_dir)
+      end
   end
 
   def lib_dir
     @lib_dir ||=
-      Dir[File.join(root_dir, 'lib/gcc/*/libgcc*')]
+      if use_nix?
-      .map { |path| File.dirname(path) }
+        File.join(root_dir, 'lib')
-      .select { |path| File.basename(path).match(/^\d+$/) }
+      else
-      .max_by { |path| File.basename(path).to_i }
+        Dir[File.join(root_dir, 'lib/gcc/*/libgcc*')]
-  end
+          .map { |path| File.dirname(path) }
-
+          .select { |path| File.basename(path).match(/^\d+$/) }
-  def relative_lib_dir
+          .max_by { |path| File.basename(path).to_i }
-    @relative_lib_dir ||= relative_dir(lib_dir, File.join(root_dir, 'lib'))
-  end
-
-  def darwin_lib_dir
-    @darwin_lib_dir ||=
-      Dir[File.join(lib_dir, 'gcc/*apple-darwin*/*')].max_by do |path|
-        [
-          File.basename(File.dirname(path)).match(/darwin(\d+)$/)[1].to_i,
-          File.basename(path).split('.').map(&:to_i)
-        ]
       end
   end
 
-  def relative_darwin_lib_dir
+  def target_lib_dir
-    @relative_darwin_lib_dir ||=
+    File.join('gcc', 'lib')
-      relative_dir(darwin_lib_dir, File.join(root_dir, 'lib'))
+  end
+
+  def darwin_lib_dir
+    return @darwin_lib_dir if @darwin_lib_dir
+
+    search_path = File.join(lib_dir, 'gcc/*apple-darwin*/*')
+
+    @darwin_lib_dir ||= Dir[search_path].max_by do |path|
+      vers = []
+
+      unless use_nix?
+        matches = File.basename(File.dirname(path)).match(/darwin(\d+)$/)
+        vers << matches[1].to_i if matches
+      end
+
+      vers << File.basename(path).split('.').map(&:to_i)
+      vers.flatten
+    end
+  end
+
+  def target_darwin_lib_dir
+    File.join('gcc', 'lib', 'apple-darwin')
   end
 
   # Sanitize folder name with full "MAJOR.MINOR.PATCH" version number to just
   # the MAJOR version. Apple's codesign CLI tool throws a "bundle format
   # unrecognized" error if there are any folders with two dots in their name
   # within the Emacs.app application bundle.
-  def sanitized_relative_darwin_lib_dir
+  def sanitized_target_darwin_lib_dir
-    @sanitized_relative_darwin_lib_dir ||=
+    @sanitized_target_darwin_lib_dir ||=
       File.join(
-        File.dirname(relative_darwin_lib_dir),
+        File.dirname(target_darwin_lib_dir),
-        File.basename(relative_darwin_lib_dir).gsub('.', '_')
+        File.basename(target_darwin_lib_dir).gsub('.', '_')
       )
   end
 
-  def app_bundle_relative_lib_dir
+  def app_bundle_target_lib_dir
-    @app_bundle_relative_lib_dir ||=
+    @app_bundle_target_lib_dir ||=
       relative_dir(
-        File.join(embedder.lib_dir, relative_lib_dir),
+        File.join(embedder.lib_dir, target_lib_dir),
         embedder.invocation_dir
       )
   end
 
-  def app_bundle_relative_darwin_lib_dir
+  def app_bundle_target_darwin_lib_dir
-    @app_bundle_relative_darwin_lib_dir ||=
+    @app_bundle_target_darwin_lib_dir ||=
       relative_dir(
-        File.join(embedder.lib_dir, sanitized_relative_darwin_lib_dir),
+        File.join(embedder.lib_dir, sanitized_target_darwin_lib_dir),
         embedder.invocation_dir
       )
   end
 
   def libgccjit_root_dir
-    @libgccjit_root_dir ||= `brew --prefix libgccjit`.chomp
+    @libgccjit_root_dir ||=
+      if use_nix?
+        ENV['NIX_LIBGCCJIT_ROOT']&.strip
+      else
+        `brew --prefix libgccjit`.chomp
+      end
   end
 
   def libgccjit_major_version
-    @libgccjit_major_version ||= File.basename(libgccjit_lib_dir.to_s)
+    @libgccjit_major_version ||=
+      if use_nix?
+        # rubocop:disable Style/SafeNavigationChainLength
+        ENV['NIX_LIBGCCJIT_VERSION']&.strip&.split('.')&.first
+        # rubocop:enable Style/SafeNavigationChainLength
+      else
+        File.basename(libgccjit_lib_dir.to_s)
+      end
   end
 
   def libgccjit_lib_dir
     @libgccjit_lib_dir ||=
-      Dir[
+      if use_nix?
-        File.join(libgccjit_root_dir, 'lib/gcc/*/libgccjit*.dylib'),
+        Dir[File.join(libgccjit_root_dir, 'lib/libgccjit*.dylib')]
-        File.join(libgccjit_root_dir, 'lib/gcc/*/libgccjit.so*')
+          .map { |path| File.dirname(path) }.first
-      ]
+      else
-      .map { |path| File.dirname(path) }
+        Dir[
-      .select { |path| File.basename(path).match(/^\d+$/) }
+          File.join(libgccjit_root_dir, 'lib/gcc/*/libgccjit*.dylib'),
-      .max_by { |path| File.basename(path).to_i }
+          File.join(libgccjit_root_dir, 'lib/gcc/*/libgccjit.so*'),
+          ]
+          .map { |path| File.dirname(path) }
+          .select { |path| File.basename(path).match(/^\d+$/) }
+          .max_by { |path| File.basename(path).to_i }
+      end
   end
 
   def verify_libgccjit
@@ -1446,6 +1701,11 @@ class GccInfo
             'brew reinstall libgccjit'
     end
 
+    # No need to verify gcc vs libgccjit for Nix, as we can pull everything we
+    # need from the libgccjit package. On homebrew we need to pull parts from
+    # gcc and parts from libgccjit, hence we need to ensure versions match.
+    return if use_nix?
+
     return if major_version == libgccjit_major_version
 
     fatal <<~TEXT
@@ -1472,6 +1732,8 @@ class GccInfo
 end
 
 if __FILE__ == $PROGRAM_NAME
+  use_nix_default = !ENV.fetch('IN_NIX_SHELL', '').empty?
+
   cli_options = {
     work_dir: File.expand_path(__dir__),
     native_full_aot: false,
@@ -1480,6 +1742,7 @@ if __FILE__ == $PROGRAM_NAME
     parallel: Etc.nprocessors,
     rsvg: true,
     dbus: true,
+    use_nix: use_nix_default,
     xwidgets: true,
     tree_sitter: true,
     fd_setsize: 10_000,
@@ -1502,6 +1765,16 @@ if __FILE__ == $PROGRAM_NAME
       Options:
     DOC
 
+    opts.on(
+      '--info',
+      'Print environment info and detected library paths, then exit'
+    ) { |v| cli_options[:info] = v }
+
+    opts.on(
+      '--preview',
+      'Print preview details about build and exit.'
+    ) { |v| cli_options[:preview] = v }
+
     opts.on(
       '-j',
       '--parallel COUNT',
@@ -1515,6 +1788,12 @@ if __FILE__ == $PROGRAM_NAME
       'branch allowing builds of old commits'
     ) { |v| cli_options[:git_sha] = v }
 
+    opts.on(
+      '--[no-]use-nix',
+      'Use Nix instead of Homebrew to find dependencies ' \
+      '(default: enabled if IN_NIX_SHELL is set)'
+    ) { |v| cli_options[:use_nix] = v }
+
     opts.on(
       '--[no-]xwidgets',
       'Enable/disable XWidgets if supported ' \
@@ -1653,7 +1932,15 @@ if __FILE__ == $PROGRAM_NAME
 
     Output.log_level = cli_options[:log_level]
     work_dir = cli_options.delete(:work_dir)
-    Build.new(work_dir, ARGV.shift, cli_options).build
+    build = Build.new(work_dir, ARGV.shift, cli_options)
+
+    if cli_options[:info]
+      build.print_info
+    elsif cli_options[:preview]
+      build.print_preview
+    else
+      build.build
+    end
   rescue Error => e
     warn "ERROR: #{e.message}"
     exit 1

flake-package-versions.txt

@@ -0,0 +1,67 @@
+DarwinTools-1
+autoconf-2.72
+bash-5.2p37
+brotli-1.1.0
+bzip2-1.0.8
+cairo-1.18.2
+cctools-binutils-darwin-1010.6
+cctools-binutils-darwin-wrapper-1010.6
+clang-16.0.6
+clang-wrapper-16.0.6
+coreutils-9.5
+curl-8.11.0
+dbus-1.14.10
+diffutils-3.10
+expat-2.6.4
+file-5.45
+findutils-4.10.0
+fontconfig-2.15.0
+freetype-2.13.3
+gawk-5.3.1
+gcc-13.3.0
+gcc-wrapper-13.3.0
+gdk-pixbuf-2.42.12
+gettext-0.21.1
+giflib-5.2.2
+git-2.47.0
+glib-2.82.1
+gnugrep-3.11
+gnumake-4.4.1
+gnused-4.9
+gnutar-1.35
+gnutls-3.8.6
+graphite2-1.3.14
+gzip-1.13
+harfbuzz-10.0.1
+jq-1.7.1
+krb5-1.21.3
+lcms2-2.16
+libdeflate-1.22
+libgccjit-13.3.0
+libiconv-107
+libidn2-2.3.7
+libjpeg-turbo-3.0.4
+libpng-apng-1.6.43
+libpsl-0.21.5
+librsvg-2.58.3
+libtasn1-4.19.0
+libtiff-4.7.0
+libwebp-1.4.0
+libxml2-2.13.4
+mailutils-3.17
+nettle-3.10
+nghttp2-1.64.0
+openssl-3.3.2
+patch-2.7.6
+pkg-config-wrapper-0.29.2
+python3-3.12.7
+rsync-3.3.0
+ruby-3.3.5
+sqlite-3.46.1
+texinfo-7.1.1
+time-1.9
+tree-sitter-0.24.3
+which-2.21
+xcbuild-0.1.1-unstable-2019-11-20
+xz-5.6.3
+zstd-1.5.6

flake.lock

@@ -0,0 +1,61 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1731533236,
+        "narHash": "sha256-l0KFg5HjrsfsO/JpG+r7fRrqm12kzFHyUHqHCVpMMbI=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "11707dc2f618dd54ca8739b309ec4fc024de578b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1731603435,
+        "narHash": "sha256-CqCX4JG7UiHvkrBTpYC3wcEurvbtTADLbo3Ns2CEoL8=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "8b27c1239e5c421a2bbc2c65d52e4a6fbf2ff296",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "24.11-beta",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,102 @@
+{
+  description = "Development environment flake";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/24.11-beta";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+
+        # List of supported macOS SDK versions.
+        sdk_versions = [ "11" "12" "13" "14" "15" ];
+        default_sdk_version = "11";
+
+        mkDevShell = { macos_version ? default_sdk_version }:
+          let
+            apple_sdk = pkgs.${"apple-sdk_${macos_version}"};
+          in
+            pkgs.mkShell {
+              # Package list specifically excludes ncurses, so that we link
+              # against the system version of ncurses. This ensures emacs' TUI
+              # works out of the box without the user having to manually set
+              # TERMINFO in the shell before launching emacs.
+              packages = with pkgs; [
+                apple_sdk
+                autoconf
+                bash
+                cairo
+                clang
+                coreutils
+                curl
+                darwin.DarwinTools # sw_vers
+                dbus
+                expat
+                findutils
+                gcc
+                gettext
+                giflib
+                git
+                gmp
+                gnumake
+                gnupatch
+                gnused
+                gnutar
+                gnutls
+                harfbuzz
+                jansson
+                jq
+                lcms2
+                libffi
+                libgccjit
+                libiconv
+                libjpeg
+                libpng
+                librsvg
+                libtasn1
+                libunistring
+                libwebp
+                libxml2
+                mailutils
+                nettle
+                pkg-config
+                python3
+                rsync
+                ruby_3_3
+                sqlite
+                texinfo
+                time
+                tree-sitter
+                which
+                xcbuild
+                zlib
+              ];
+
+              shellHook = ''
+                export CC=clang
+                export MACOSX_DEPLOYMENT_TARGET="${macos_version}.0"
+                export DEVELOPER_DIR="${apple_sdk}"
+                export NIX_LIBGCCJIT_VERSION="${pkgs.libgccjit.version}"
+                export NIX_LIBGCCJIT_ROOT="${pkgs.libgccjit.outPath}"
+                export BUNDLE_WITHOUT=development
+              '';
+            };
+
+        # Generate an attrset of shells for each macOS SDK version.
+        versionShells = builtins.listToAttrs (
+          map (version: {
+            name = "macos${version}";
+            value = mkDevShell { macos_version = version; };
+          }) sdk_versions
+        );
+      in
+        {
+          devShells = versionShells // {
+            default = mkDevShell {};
+          };
+        }
+    );
+}

go.mod

@@ -1,6 +1,6 @@
 module github.com/jimeh/build-emacs-for-macos
 
-go 1.20
+go 1.23
 
 require (
 	github.com/bearer/gon v0.0.36

go.sum

@@ -24,6 +24,7 @@ github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/go-github/v35 v35.3.0 h1:fU+WBzuukn0VssbayTT+Zo3/ESKX9JYWjbZTLOTEyho=
 github.com/google/go-github/v35 v35.3.0/go.mod h1:yWB7uCcVWaUbUP74Aq3whuMySRMatyRmq5U9FTNlbio=
 github.com/google/go-querystring v1.0.0/go.mod h1:odCYkC5MyYFN7vkCjXpyrEuKhc/BUO6wN/zVPAxq5ck=

pkg/dmgbuild/license.go

@@ -116,7 +116,6 @@ func NewLicense() License {
 	return License{}
 }
 
-//nolint:goconst
 func (s *License) Render() []string {
 	var l []string
 

pkg/osinfo/osinfo.go

@@ -1,41 +1,65 @@
 package osinfo
 
 import (
+	"os"
 	"os/exec"
 	"strconv"
 	"strings"
 )
 
 type OSInfo struct {
-	Name    string `yaml:"name" json:"name"`
+	Name       string `yaml:"name" json:"name"`
-	Version string `yaml:"version" json:"version"`
+	Version    string `yaml:"version" json:"version"`
-	Arch    string `yaml:"arch" json:"arch"`
+	SDKVersion string `yaml:"sdk_version" json:"sdk_version"`
+	Arch       string `yaml:"arch" json:"arch"`
 }
 
 func New() (*OSInfo, error) {
-	version, err := exec.Command("sw_vers", "-productVersion").CombinedOutput()
+	version, err := exec.Command("sw_vers", "-productVersion").Output()
 	if err != nil {
 		return nil, err
 	}
 
+	sdkVersion := os.Getenv("MACOSX_DEPLOYMENT_TARGET")
+	if sdkVersion == "" {
+		var ver []byte
+		ver, err = exec.Command("xcrun", "--show-sdk-version").Output()
+		if err != nil {
+			return nil, err
+		}
+
+		sdkVersion = string(ver)
+	}
+
 	arch, err := exec.Command("uname", "-m").CombinedOutput()
 	if err != nil {
 		return nil, err
 	}
 
 	return &OSInfo{
-		Name:    "macOS",
+		Name:       "macOS",
-		Version: strings.TrimSpace(string(version)),
+		Version:    strings.TrimSpace(string(version)),
-		Arch:    strings.TrimSpace(string(arch)),
+		SDKVersion: strings.TrimSpace(sdkVersion),
+		Arch:       strings.TrimSpace(string(arch)),
 	}, nil
 }
 
-// DistinctVersion returns macOS version down to a distinct "major"
+// DistinctVersion returns macOS version down to a distinct "major" version. For
-// version. For macOS 10.x, this will include the first two numeric parts of the
+// macOS 10.x, this will include the first two numeric parts of the version
-// version (10.15), while for 11.x and later, the first numeric part is enough
+// (10.15), while for 11.x and later, the first numeric part is enough (11).
-// (11).
 func (s *OSInfo) DistinctVersion() string {
-	parts := strings.Split(s.Version, ".")
+	return s.distinctVersion(s.Version)
+}
+
+// DistinctSDKVersion returns macOS version down to a distinct "major" version.
+// For macOS 10.x, this will include the first two numeric parts of the version
+// (10.15), while for 11.x and later, the first numeric part is enough (11).
+func (s *OSInfo) DistinctSDKVersion() string {
+	return s.distinctVersion(s.SDKVersion)
+}
+
+func (s *OSInfo) distinctVersion(version string) string {
+	parts := strings.Split(version, ".")
 
 	if n, _ := strconv.Atoi(parts[0]); n >= 11 {
 		return parts[0]

pkg/plan/create.go

@@ -95,10 +95,17 @@ func Create(ctx context.Context, opts *Options) (*Plan, error) { //nolint:funlen
 		releaseName = "Emacs." + version
 	}
 
+	// Attempt to get the macOS SDK version from the environment, if it's not
+	// available, use the version from the system.
+	targetMacOSVersion := osInfo.DistinctSDKVersion()
+	if targetMacOSVersion == "" {
+		targetMacOSVersion = osInfo.DistinctVersion()
+	}
+
 	buildName := fmt.Sprintf(
 		"Emacs.%s.%s.%s",
 		absoluteVersion,
-		sanitize.String(osInfo.Name+"-"+osInfo.DistinctVersion()),
+		sanitize.String(osInfo.Name+"-"+targetMacOSVersion),
 		sanitize.String(osInfo.Arch),
 	)
 	diskImage := buildName + ".dmg"

pkg/sign/emacs.go

@@ -123,7 +123,7 @@ func signCLIHelper(ctx context.Context, appBundle string, opts *Options) error {
 // app bundle itself.
 func elnFiles(emacsApp string) ([]string, error) {
 	var files []string
-	walkDirFunc := func(path string, d fs.DirEntry, _err error) error {
+	walkDirFunc := func(path string, d fs.DirEntry, _ error) error {
 		if d.Type().IsRegular() && strings.HasSuffix(path, ".eln") &&
 			!strings.Contains(path, ".app/Contents/Frameworks/") {
 			files = append(files, path)