feat: add bun as optional dependency (no global install required)

- Add @oven/bun-* platform packages as optionalDependencies
- Create postinstall script to set up bun binary from optional deps
- Handle Windows ARM64 by downloading x64-baseline for emulation
- Remove setup-bun from CI workflows (npm install handles it now)
- Remove manual Bun install instructions from docs

This alternative approach eliminates the need for global Bun installation
or setup-bun action in CI. npm install automatically installs the
platform-appropriate bun binary.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: ochafik

.github/workflows/ci.yml

@@ -23,8 +23,6 @@ jobs:
             name: Windows x64
           - os: windows-11-arm
             name: Windows ARM64
-            # Use x64-baseline build via emulation (native ARM64 not yet available)
-            bun-download-url: https://github.com/oven-sh/bun/releases/latest/download/bun-windows-x64-baseline.zip
           - os: macos-latest
             name: macOS ARM64
 
@@ -38,11 +36,6 @@ jobs:
         shell: bash
         run: '! grep -E "\"resolved\": \"https?://" package-lock.json | grep -v registry.npmjs.org'
 
-      - uses: oven-sh/setup-bun@v2
-        with:
-          bun-version: latest
-          bun-download-url: ${{ matrix.bun-download-url }}
-
       - uses: actions/setup-node@v4
         with:
           node-version: "20"
@@ -78,23 +71,16 @@ jobs:
         with:
           distribution: Ubuntu-24.04
 
-      - name: Install dependencies in WSL
+      - name: Install Node.js in WSL
         shell: wsl-bash {0}
         run: |
-          # Install Node.js and Bun
           sudo apt-get update
-          sudo apt-get install -y unzip
           curl -fsSL https://deb.nodesource.com/setup_20.x | sudo -E bash -
           sudo apt-get install -y nodejs
-          curl -fsSL https://bun.sh/install | bash
-          echo 'export BUN_INSTALL="$HOME/.bun"' >> ~/.bashrc
-          echo 'export PATH="$BUN_INSTALL/bin:$PATH"' >> ~/.bashrc
 
       - name: Build and test in WSL
         shell: wsl-bash {0}
         run: |
-          export BUN_INSTALL="$HOME/.bun"
-          export PATH="$BUN_INSTALL/bin:$PATH"
           npm install
           npm run build
           npm test
@@ -114,19 +100,13 @@ jobs:
             name: Windows x64
           - os: windows-11-arm
             name: Windows ARM64
-            bun-download-url: https://github.com/oven-sh/bun/releases/latest/download/bun-windows-x64-baseline.zip
           - os: macos-latest
             name: macOS ARM64
 
     name: Test git install (${{ matrix.name }})
     runs-on: ${{ matrix.os }}
 
     steps:
-      - uses: oven-sh/setup-bun@v2
-        with:
-          bun-version: latest
-          bun-download-url: ${{ matrix.bun-download-url }}
-
       - uses: actions/setup-node@v4
         with:
           node-version: "20"

.github/workflows/publish.yml

@@ -14,9 +14,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: oven-sh/setup-bun@v2
-        with:
-          bun-version: latest
       - uses: actions/setup-node@v4
         with:
           node-version: 22

CONTRIBUTING.md

@@ -2,39 +2,6 @@
 
 We welcome contributions to the MCP Apps SDK! This document outlines the process for contributing to the project.
 
-## Prerequisites
-
-Development requires [Bun](https://bun.sh) (used for building and testing).
-
-<details>
-<summary><strong>macOS / Linux</strong></summary>
-
-```bash
-curl -fsSL https://bun.sh/install | bash
-```
-
-</details>
-
-<details>
-<summary><strong>Windows (native)</strong></summary>
-
-```powershell
-powershell -c "irm bun.sh/install.ps1 | iex"
-```
-
-> **ARM64 note**: Native binaries aren't available yet; the x64 build runs via emulation.
-
-</details>
-
-<details>
-<summary><strong>Windows (WSL)</strong></summary>
-
-```bash
-curl -fsSL https://bun.sh/install | bash
-```
-
-</details>
-
 ## Getting Started
 
 1. Fork the repository

README.md

@@ -56,7 +56,6 @@ The [`examples/`](https://github.com/modelcontextprotocol/ext-apps/tree/main/exa
 To run all examples together:
 
 ```bash
-# Bun is required for development (see CONTRIBUTING.md for install instructions)
 npm install
 npm run examples:start
 ```