Replace ghostty git submodule with Zig URL dependency

Ghostty is now fetched automatically by Zig's package manager from a
pinned GitHub archive URL instead of requiring a git submodule.  This
makes `zig build` fully self-contained — no submodule init needed.

- build.zig.zon: replace .path dependency with .url + .hash pointing
  to ghostty commit 0182541 (latest as of 2026-04-13)
- build.zig: get ghostty headers from the artifact's emitted include
  tree instead of hardcoded vendor/ghostty/include path
- Remove .gitmodules and vendor/ghostty submodule
- CI/release workflows: drop submodule checkout steps
- README: update build instructions, document --override-dep for
  local ghostty development

MELPA users can now compile from source with just `zig build` since
the ghostty dependency is fetched on demand.

Author: dakra

.github/workflows/ci.yml

@@ -97,15 +97,6 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4
-        with:
-          submodules: recursive
-          persist-credentials: true
-
-      - name: Rewrite SSH to HTTPS for submodules
-        run: |
-          git config --global url."https://github.com/".insteadOf "git@github.com:"
-          git submodule sync --recursive
-          git submodule update --init --recursive
 
       - name: Install Zig
         uses: mlugg/setup-zig@v2

.github/workflows/release.yml

@@ -28,15 +28,6 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4
-        with:
-          submodules: recursive
-          persist-credentials: true
-
-      - name: Rewrite SSH to HTTPS for submodules
-        run: |
-          git config --global url."https://github.com/".insteadOf "git@github.com:"
-          git submodule sync --recursive
-          git submodule update --init --recursive
 
       - name: Install Zig
         uses: mlugg/setup-zig@v2

.gitmodules

@@ -94,48 +94,31 @@ require local Emacs headers.  If you want to override the vendored header, set
 `../include` and `../share/emacs/include`.
 
 ```sh
-# Clone with submodule
-git clone --recurse-submodules https://github.com/dakra/ghostel.git
+git clone https://github.com/dakra/ghostel.git
 cd ghostel
 
-# Optional: override the vendored header
-# export EMACS_INCLUDE_DIR=/path/to/include
-# export EMACS_BIN_DIR=/path/to/emacs/bin
-
-# Build everything (libghostty-vt + ghostel module)
+# Build everything (fetches ghostty automatically via Zig package manager)
 zig build -Doptimize=ReleaseFast
 ```
 
-If you already have the repo, initialize the submodule and build:
+To override the vendored Emacs header, set `EMACS_INCLUDE_DIR` to a
+directory containing `emacs-module.h`, or set `EMACS_BIN_DIR` to an
+Emacs `bin/` directory.
+
+To build against a local ghostty checkout:
 
 ```sh
-git submodule update --init --recursive vendor/ghostty
-zig build -Doptimize=ReleaseFast
+zig build -Doptimize=ReleaseFast --override-dep ghostty=/path/to/ghostty
 ```
 
 ### Building from source (MELPA install)
 
-MELPA packages only include `.el` files — `build.zig`, the vendored header,
-Zig sources, and the ghostty submodule are not included.  This means
-`M-x ghostel-module-compile`
-is not available when installed from MELPA.
-
-The recommended approach is to download a **pre-built binary** via
-`M-x ghostel-download-module` (this works regardless of install method).
-
-If you prefer to compile from source, clone the repository, build, and copy
-the resulting module into your MELPA package directory:
+When installed from MELPA, `M-x ghostel-module-compile` builds the native
+module from source using `zig build`.  Zig's package manager fetches the
+ghostty dependency automatically — no git submodule needed.
 
-```sh
-git clone --recurse-submodules https://github.com/dakra/ghostel.git
-cd ghostel
-zig build -Doptimize=ReleaseFast
-
-# Copy the module into your MELPA package directory
-# (adjust the path to match your Emacs package directory and ghostel version)
-cp ghostel-module.dylib ~/.emacs.d/elpa/ghostel-*/    # macOS
-cp ghostel-module.so    ~/.emacs.d/elpa/ghostel-*/    # Linux
-```
+Alternatively, download a **pre-built binary** via
+`M-x ghostel-download-module`.
 
 ## Shell Integration
 

README.md

@@ -12,10 +12,9 @@ pub fn build(b: *std.Build) void {
         .target = target,
         .optimize = optimize,
         .@"emit-lib-vt" = true,
-    }) orelse std.debug.panic(
-        "ghostty dependency unavailable; initialize the vendor/ghostty submodule",
-        .{},
-    );
+    }) orelse @panic("ghostty dependency unavailable; run: zig build --fetch");
+
+    const ghostty_lib = ghostty_dep.artifact("ghostty-vt-static");
 
     const mod = b.createModule(.{
         .root_source_file = b.path("src/module.zig"),
@@ -25,8 +24,8 @@ pub fn build(b: *std.Build) void {
         .strip = if (is_release) true else null,
         .omit_frame_pointer = if (is_release) true else null,
     });
-    addModuleIncludes(b, mod, emacs_module_dir);
-    mod.linkLibrary(ghostty_dep.artifact("ghostty-vt-static"));
+    addModuleIncludes(mod, emacs_module_dir, ghostty_lib);
+    mod.linkLibrary(ghostty_lib);
 
     const lib = b.addLibrary(.{
         .name = "ghostel-module",
@@ -58,7 +57,7 @@ pub fn build(b: *std.Build) void {
         .optimize = optimize,
         .link_libc = true,
     });
-    addModuleIncludes(b, check_mod, emacs_module_dir);
+    addModuleIncludes(check_mod, emacs_module_dir, ghostty_lib);
 
     const check_obj = b.addObject(.{
         .name = "ghostel-module-check",
@@ -70,12 +69,12 @@ pub fn build(b: *std.Build) void {
 }
 
 fn addModuleIncludes(
-    b: *std.Build,
     mod: *std.Build.Module,
     emacs_module_dir: std.Build.LazyPath,
+    ghostty_lib: *std.Build.Step.Compile,
 ) void {
     mod.addSystemIncludePath(emacs_module_dir);
-    mod.addIncludePath(b.path("vendor/ghostty/include"));
+    mod.addIncludePath(ghostty_lib.getEmittedIncludeTree());
 }
 
 fn resolveEmacsModuleDir(b: *std.Build) std.Build.LazyPath {

build.zig

@@ -4,6 +4,10 @@
     .paths = .{""},
     .fingerprint = 0x5a44bdd1198a0f4b,
     .dependencies = .{
-        .ghostty = .{ .path = "./vendor/ghostty", .lazy = true },
+        .ghostty = .{
+            .url = "https://github.com/ghostty-org/ghostty/archive/01825411ab2720e47e6902e9464e805bc6a062a1.tar.gz",
+            .hash = "ghostty-1.3.2-dev-5UdBCzaaBwVjJOr-ltYINjybeEOAmLAauH5oq8-cdNGN",
+            .lazy = true,
+        },
     },
 }