From f3a4e4db436e974c573848e1b5deab0c4e20e65c Mon Sep 17 00:00:00 2001
From: Lawrence Chen <54008264+lawrencecchen@users.noreply.github.com>
Date: Fri, 20 Feb 2026 14:30:31 -0800
Subject: [PATCH] Cache GhosttyKit builds by ghostty commit in setup script
 (#204)

---
 scripts/setup.sh | 54 +++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 47 insertions(+), 7 deletions(-)

diff --git a/scripts/setup.sh b/scripts/setup.sh
index 10413872..2f4f6d2a 100755
--- a/scripts/setup.sh
+++ b/scripts/setup.sh
@@ -1,5 +1,5 @@
-#!/bin/bash
-set -e
+#!/usr/bin/env bash
+set -euo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
@@ -16,13 +16,53 @@ if ! command -v zig &> /dev/null; then
     exit 1
 fi
 
-echo "==> Building GhosttyKit.xcframework (this may take a few minutes)..."
-cd ghostty
-zig build -Demit-xcframework=true -Doptimize=ReleaseFast
-cd "$PROJECT_DIR"
+GHOSTTY_SHA="$(git -C ghostty rev-parse HEAD)"
+CACHE_ROOT="${CMUX_GHOSTTYKIT_CACHE_DIR:-$HOME/.cache/cmux/ghosttykit}"
+CACHE_DIR="$CACHE_ROOT/$GHOSTTY_SHA"
+CACHE_XCFRAMEWORK="$CACHE_DIR/GhosttyKit.xcframework"
+LOCAL_XCFRAMEWORK="$PROJECT_DIR/ghostty/macos/GhosttyKit.xcframework"
+LOCK_DIR="$CACHE_ROOT/$GHOSTTY_SHA.lock"
+
+mkdir -p "$CACHE_ROOT"
+
+echo "==> Ghostty submodule commit: $GHOSTTY_SHA"
+
+while ! mkdir "$LOCK_DIR" 2>/dev/null; do
+    echo "==> Waiting for GhosttyKit cache lock for $GHOSTTY_SHA..."
+    sleep 1
+done
+trap 'rmdir "$LOCK_DIR" >/dev/null 2>&1 || true' EXIT
+
+if [ -d "$CACHE_XCFRAMEWORK" ]; then
+    echo "==> Reusing cached GhosttyKit.xcframework"
+else
+    if [ -d "$LOCAL_XCFRAMEWORK" ]; then
+        echo "==> Seeding cache from existing local GhosttyKit.xcframework"
+    else
+        echo "==> Building GhosttyKit.xcframework (this may take a few minutes)..."
+        (
+            cd ghostty
+            zig build -Demit-xcframework=true -Doptimize=ReleaseFast
+        )
+    fi
+
+    SRC_XCFRAMEWORK="$LOCAL_XCFRAMEWORK"
+    if [ ! -d "$SRC_XCFRAMEWORK" ]; then
+        echo "Error: GhosttyKit.xcframework not found at $SRC_XCFRAMEWORK"
+        exit 1
+    fi
+
+    TMP_DIR="$(mktemp -d "$CACHE_ROOT/.ghosttykit-tmp.XXXXXX")"
+    mkdir -p "$CACHE_DIR"
+    cp -R "$SRC_XCFRAMEWORK" "$TMP_DIR/GhosttyKit.xcframework"
+    rm -rf "$CACHE_XCFRAMEWORK"
+    mv "$TMP_DIR/GhosttyKit.xcframework" "$CACHE_XCFRAMEWORK"
+    rmdir "$TMP_DIR"
+    echo "==> Cached GhosttyKit.xcframework at $CACHE_XCFRAMEWORK"
+fi
 
 echo "==> Creating symlink for GhosttyKit.xcframework..."
-ln -sf ghostty/macos/GhosttyKit.xcframework GhosttyKit.xcframework
+ln -sfn "$CACHE_XCFRAMEWORK" GhosttyKit.xcframework
 
 echo "==> Setup complete!"
 echo ""