Add libghostty-vt source tarball (2.8 MB vs. 38 MB for Ghostty GUI) (#11863)

This makes it so that `zig build dist -Demit-lib-vt` produces a
`libghostty-vt-<version>.tar.gz` source tarball that only contains what
is needed to build and test libghostty-vt (it cannot build Ghostty GUI
on macOS or Linux). `distcheck` has been updated to also verify cmake
works.

The source tarball goes from 38 MB to 2.8 MB for libghostty.

I also updated CI to build and test this, and also contains an assertion
that our tarball is always less than 5 MB so we can be aware if/when we
blow it up.

The `release-tip` job was also updated to add the libghostty-vt tarball
to our tip release on GH.

.github/workflows/release-tip.yml

@@ -163,7 +163,7 @@ jobs:
           github.ref_name == 'main'
         )
       )
-    runs-on: namespace-profile-ghostty-md
+    runs-on: namespace-profile-ghostty-sm
     env:
       ZIG_LOCAL_CACHE_DIR: /zig/local-cache
       ZIG_GLOBAL_CACHE_DIR: /zig/global-cache
@@ -206,6 +206,60 @@ jobs:
             ghostty-source.tar.gz.minisig
           token: ${{ secrets.GH_RELEASE_TOKEN }}
 
+  source-tarball-lib-vt:
+    needs: [setup]
+    if: |
+      needs.setup.outputs.should_skip != 'true' &&
+      (
+        github.event_name == 'workflow_dispatch' ||
+        (
+          github.repository_owner == 'ghostty-org' &&
+          github.ref_name == 'main'
+        )
+      )
+    runs-on: namespace-profile-ghostty-sm
+    env:
+      ZIG_LOCAL_CACHE_DIR: /zig/local-cache
+      ZIG_GLOBAL_CACHE_DIR: /zig/global-cache
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - name: Setup Cache
+        uses: namespacelabs/nscloud-cache-action@a90bb5d4b27522ce881c6e98eebd7d7e6d1653f9 # v1.4.2
+        with:
+          path: |
+            /nix
+            /zig
+      - uses: cachix/install-nix-action@51f3067b56fe8ae331890c77d4e454f6d60615ff # v31.10.2
+        with:
+          nix_path: nixpkgs=channel:nixos-unstable
+      - uses: cachix/cachix-action@1eb2ef646ac0255473d23a5907ad7b04ce94065c # v17
+        with:
+          name: ghostty
+          authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
+      - name: Create Tarball
+        run: |
+          rm -rf zig-out/dist
+          nix develop -c zig build dist -Demit-lib-vt=true
+          cp zig-out/dist/*.tar.gz libghostty-vt-source.tar.gz
+
+      - name: Sign Tarball
+        run: |
+          echo -n "${{ secrets.MINISIGN_KEY }}" > minisign.key
+          echo -n "${{ secrets.MINISIGN_PASSWORD }}" > minisign.password
+          nix develop -c minisign -S -m libghostty-vt-source.tar.gz -s minisign.key < minisign.password
+
+      - name: Update Release
+        uses: softprops/action-gh-release@153bb8e04406b158c6c84fc1615b65b24149a1fe # v2.6.1
+        with:
+          name: 'Ghostty Tip ("Nightly")'
+          prerelease: true
+          tag_name: tip
+          target_commitish: ${{ github.sha }}
+          files: |
+            libghostty-vt-source.tar.gz
+            libghostty-vt-source.tar.gz.minisig
+          token: ${{ secrets.GH_RELEASE_TOKEN }}
+
   build-macos:
     needs: [setup]
     if: |

.github/workflows/test.yml

@@ -85,6 +85,7 @@ jobs:
       - skip
       - build-bench
       - build-dist
+      - build-dist-lib-vt
       - build-examples-zig
       - build-examples-cmake
       - build-examples-cmake-windows
@@ -652,7 +653,7 @@ jobs:
         run: nm result/bin/.ghostty-wrapped 2>&1 | grep -q 'main_ghostty.main'
 
   build-dist:
-    runs-on: namespace-profile-ghostty-md
+    runs-on: namespace-profile-ghostty-sm
     needs: test
     outputs:
       artifact-id: ${{ steps.upload-artifact.outputs.artifact-id }}
@@ -693,6 +694,48 @@ jobs:
           path: |-
             ghostty-source.tar.gz
 
+  build-dist-lib-vt:
+    runs-on: namespace-profile-ghostty-sm
+    needs: test
+    env:
+      ZIG_LOCAL_CACHE_DIR: /zig/local-cache
+      ZIG_GLOBAL_CACHE_DIR: /zig/global-cache
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+
+      - name: Setup Cache
+        uses: namespacelabs/nscloud-cache-action@a90bb5d4b27522ce881c6e98eebd7d7e6d1653f9 # v1.4.2
+        with:
+          path: |
+            /nix
+            /zig
+
+      # Install Nix and use that to run our tests so our environment matches exactly.
+      - uses: cachix/install-nix-action@51f3067b56fe8ae331890c77d4e454f6d60615ff # v31.10.2
+        with:
+          nix_path: nixpkgs=channel:nixos-unstable
+      - uses: cachix/cachix-action@1eb2ef646ac0255473d23a5907ad7b04ce94065c # v17
+        with:
+          name: ghostty
+          authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
+
+      - name: Build and Check Source Tarball
+        run: |
+          rm -rf zig-out/dist
+          nix develop -c zig build distcheck -Demit-lib-vt=true
+
+      - name: Verify tarball size
+        run: |
+          tarball=$(ls zig-out/dist/*.tar.gz)
+          size=$(stat --format=%s "$tarball")
+          max=$((5 * 1024 * 1024))
+          echo "Tarball size: $size bytes (max: $max)"
+          if [ "$size" -gt "$max" ]; then
+            echo "ERROR: tarball exceeds 5 MB"
+            exit 1
+          fi
+
   trigger-snap:
     if: github.event_name != 'pull_request'
     runs-on: namespace-profile-ghostty-xsm

src/build/GhosttyDist.zig

@@ -18,17 +18,23 @@ archive_step: *std.Build.Step,
 check_step: *std.Build.Step,
 
 pub fn init(b: *std.Build, cfg: *const Config) !GhosttyDist {
+    // The name prefix used for all paths in the archive.
+    const name = if (cfg.emit_lib_vt) "libghostty-vt" else "ghostty";
+
     // Get the resources we're going to inject into the source tarball.
+    // lib-vt doesn't need GTK resources or frame data.
     const alloc = b.allocator;
     var resources: std.ArrayListUnmanaged(Resource) = .empty;
-    {
-        const gtk = SharedDeps.gtkNgDistResources(b);
-        try resources.append(alloc, gtk.resources_c);
-        try resources.append(alloc, gtk.resources_h);
-    }
-    {
-        const framedata = GhosttyFrameData.distResources(b);
-        try resources.append(alloc, framedata.framedata);
+    if (!cfg.emit_lib_vt) {
+        {
+            const gtk = SharedDeps.gtkNgDistResources(b);
+            try resources.append(alloc, gtk.resources_c);
+            try resources.append(alloc, gtk.resources_h);
+        }
+        {
+            const framedata = GhosttyFrameData.distResources(b);
+            try resources.append(alloc, framedata.framedata);
+        }
     }
 
     // git archive to create the final tarball. "git archive" is the
@@ -46,8 +52,8 @@ pub fn init(b: *std.Build, cfg: *const Config) !GhosttyDist {
         const version = b.addWriteFiles().add("VERSION", b.fmt("{f}", .{cfg.version}));
         // --add-file uses the most recent --prefix to determine the path
         // in the archive to copy the file (the directory only).
-        git_archive.addArg(b.fmt("--prefix=ghostty-{f}/", .{
-            cfg.version,
+        git_archive.addArg(b.fmt("--prefix={s}-{f}/", .{
+            name, cfg.version,
         }));
         git_archive.addPrefixedFileArg("--add-file=", version);
     }
@@ -65,8 +71,8 @@ pub fn init(b: *std.Build, cfg: *const Config) !GhosttyDist {
 
         // --add-file uses the most recent --prefix to determine the path
         // in the archive to copy the file (the directory only).
-        git_archive.addArg(b.fmt("--prefix=ghostty-{f}/{s}/", .{
-            cfg.version,
+        git_archive.addArg(b.fmt("--prefix={s}-{f}/{s}/", .{
+            name,                                 cfg.version,
             std.fs.path.dirname(resource.dist).?,
         }));
         git_archive.addPrefixedFileArg("--add-file=", copied);
@@ -77,19 +83,28 @@ pub fn init(b: *std.Build, cfg: *const Config) !GhosttyDist {
         // This is important. Standard source tarballs extract into
         // a directory named `project-version`. This is expected by
         // standard tooling such as debhelper and rpmbuild.
-        b.fmt("--prefix=ghostty-{f}/", .{cfg.version}),
+        b.fmt("--prefix={s}-{f}/", .{ name, cfg.version }),
         "-o",
     });
     const output = git_archive.addOutputFileArg(b.fmt(
-        "ghostty-{f}.tar.gz",
-        .{cfg.version},
+        "{s}-{f}.tar.gz",
+        .{ name, cfg.version },
     ));
     git_archive.addArg("HEAD");
 
+    // When building for lib-vt only, exclude large directories that
+    // are not needed to build libghostty-vt. This significantly reduces
+    // the size of the resulting archive.
+    if (cfg.emit_lib_vt) {
+        for (lib_vt_excludes) |exclude| {
+            git_archive.addArg(b.fmt(":(exclude){s}", .{exclude}));
+        }
+    }
+
     // The install step to put the dist into the build directory.
     const install = b.addInstallFile(
         output,
-        b.fmt("dist/ghostty-{f}.tar.gz", .{cfg.version}),
+        b.fmt("dist/{s}-{f}.tar.gz", .{ name, cfg.version }),
     );
 
     // The check step to ensure the archive works.
@@ -100,8 +115,8 @@ pub fn init(b: *std.Build, cfg: *const Config) !GhosttyDist {
     // This is the root Ghostty source dir of the extracted source tarball.
     // i.e. this is way `build.zig` is.
     const extract_dir = check
-        .addOutputDirectoryArg("ghostty")
-        .path(b, b.fmt("ghostty-{f}", .{cfg.version}));
+        .addOutputDirectoryArg(name)
+        .path(b, b.fmt("{s}-{f}", .{ name, cfg.version }));
 
     // Check that tests pass within the extracted directory. This isn't
     // a fully hermetic test because we're sharing the Zig cache. In
@@ -109,7 +124,12 @@ pub fn init(b: *std.Build, cfg: *const Config) !GhosttyDist {
     // in the interest of speed we don't do that for now and hope other
     // CI catches any issues.
     const check_test = step: {
-        const step = b.addSystemCommand(&.{ "zig", "build", "test" });
+        // For lib-vt, we run the lib-vt tests instead of the full test suite.
+        const check_cmd = if (cfg.emit_lib_vt)
+            &[_][]const u8{ "zig", "build", "test-lib-vt", "-Demit-lib-vt=true" }
+        else
+            &[_][]const u8{ "zig", "build", "test" };
+        const step = b.addSystemCommand(check_cmd);
         step.setCwd(extract_dir);
 
         // Must be set so that Zig knows that this command doesn't
@@ -133,6 +153,23 @@ pub fn init(b: *std.Build, cfg: *const Config) !GhosttyDist {
         check_test.step.dependOn(&check_path.step);
     }
 
+    // For lib-vt, also verify the CMake build works from the tarball.
+    if (cfg.emit_lib_vt) {
+        const cmake_build_dir = extract_dir.path(b, "cmake-build");
+        const cmake_configure = b.addSystemCommand(&.{ "cmake", "-B" });
+        cmake_configure.addDirectoryArg(cmake_build_dir);
+        cmake_configure.setCwd(extract_dir);
+        cmake_configure.expectExitCode(0);
+        cmake_configure.step.dependOn(&check.step);
+
+        const cmake_build = b.addSystemCommand(&.{ "cmake", "--build" });
+        cmake_build.addDirectoryArg(cmake_build_dir);
+        cmake_build.expectExitCode(0);
+        cmake_build.step.dependOn(&cmake_configure.step);
+
+        check_test.step.dependOn(&cmake_build.step);
+    }
+
     return .{
         .archive = output,
         .install_step = &install.step,
@@ -141,6 +178,36 @@ pub fn init(b: *std.Build, cfg: *const Config) !GhosttyDist {
     };
 }
 
+/// Paths to exclude from the dist archive when building for lib-vt only.
+/// These are large files and directories that are not needed to build or
+/// test libghostty-vt, specified as git pathspec exclude patterns.
+const lib_vt_excludes = &[_][]const u8{
+    // App and platform resources
+    "images",
+    "macos",
+    "dist/doxygen",
+    "dist/linux",
+    "dist/macos",
+    "dist/windows",
+    "flatpak",
+    "snap",
+    "po",
+    "example",
+
+    // Test corpus (lib-vt tests use embedded testdata within src/terminal/)
+    "test",
+
+    // Large binary assets
+    "src/font/res",
+    "src/crash/testdata",
+    "pkg/wuffs/src/too_big.jpg",
+    "pkg/wuffs/src/too_big.png",
+    "pkg/breakpad/vendor",
+
+    // Vendored libraries not used by lib-vt
+    "vendor",
+};
+
 /// A dist resource is a resource that is built and distributed as part
 /// of the source tarball with Ghostty. These aren't committed to the Git
 /// repository but are built as part of the `zig build dist` command.