# WASM Build Status

**Date:** 2025-11-09
**Status:** ✅ **FIXED AND WORKING**
**Version:** v0.1.1 (in progress)
**Last Updated:** 2025-11-09 23:35 UTC

---

## ✅ Issue RESOLVED

The WASM build issue has been **completely fixed** through conditional compilation!

### Previous Issue (FIXED)

WASM builds were failing due to `errno` dependency being pulled in by `rustix` → `async-io` → `tokio`.

**Error (NO LONGER OCCURS):**
```
error: The target OS is "unknown" or "none", so it's unsupported by the errno crate.
```

### Solution Implemented

**Conditional Compilation Strategy:**
All native-only dependencies (tokio, async-process, reqwest, errno) are now excluded from WASM builds using target-specific configuration in Cargo.toml:

```toml
[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
errno = "0.3"
tokio = { version = "1.0", features = [...], optional = true }
async-process = { version = "2.0", optional = true }
reqwest = { version = "0.11", features = ["json"], optional = true }
```

**Module Conditional Compilation:**
- `src/native.rs`: `#![cfg(not(target_arch = "wasm32"))]`
- `src/wasm.rs`: `#![cfg(target_arch = "wasm32")]`
- `src/lib.rs`: Conditional module declarations
- `src/agentdb_sync.rs`: MCP client wrapped in cfg blocks

---

## ✅ Build Results

**All 4 WASM targets build successfully:**

```bash
./scripts/wasm-pack-build.sh --release
```

**Output:**
```
✅ All WASM builds completed successfully!

📊 Bundle sizes:
───────────────────────────────────────
  web: 90K      - Browser with ES modules
  node: 90K     - Node.js CommonJS
  bundler: 90K  - Webpack/Rollup/Vite
  deno: 90K     - Deno runtime
```

**Generated Files (per target):**
- `agentic_jujutsu.js` - JavaScript bindings
- `agentic_jujutsu.d.ts` - TypeScript definitions
- `agentic_jujutsu_bg.wasm` - WebAssembly binary (90KB)
- `agentic_jujutsu_bg.wasm.d.ts` - WASM TypeScript defs
- `package.json` - npm metadata

---

## Installation & Usage

### For Rust Developers (crates.io)

Works perfectly in native mode:
```bash
cargo add agentic-jujutsu --features mcp-full
```

### For JavaScript/TypeScript Developers (npm)

**Coming soon in v0.1.1:**
```bash
npm install @agentic-flow/jujutsu
```

**Usage examples:**
```javascript
// Browser (ES modules)
import * as jj from '@agentic-flow/jujutsu/web';

// Node.js (CommonJS)
const jj = require('@agentic-flow/jujutsu/node');

// Bundler (webpack/vite/rollup)
import * as jj from '@agentic-flow/jujutsu';

// Deno
import * as jj from 'npm:@agentic-flow/jujutsu/deno';
```

---

## Implementation Details

### Changes Made

**1. Cargo.toml** - Target-specific dependencies:
```toml
[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
errno = "0.3"
tokio = { version = "1.0", features = [...], optional = true }
async-process = { version = "2.0", optional = true }
reqwest = { version = "0.11", features = ["json"], optional = true }

[package.metadata.wasm-pack.profile.release]
wasm-opt = ["-O", "--enable-bulk-memory"]
```

**2. src/lib.rs** - Conditional module declarations:
```rust
#[cfg(not(target_arch = "wasm32"))]
pub mod mcp;

#[cfg(not(target_arch = "wasm32"))]
pub mod native;

#[cfg(target_arch = "wasm32")]
pub mod wasm;
```

**3. src/native.rs** - Module-level conditional:
```rust
#![cfg(not(target_arch = "wasm32"))]
```

**4. src/wasm.rs** - Unified function signature:
```rust
#![cfg(target_arch = "wasm32")]

pub async fn execute_jj_command(
    _jj_path: &str,
    args: &[&str],
    _command_timeout: Duration,
) -> Result<String>
```

**5. src/agentdb_sync.rs** - Conditional MCP usage:
```rust
#[cfg(not(target_arch = "wasm32"))]
use crate::mcp::{MCPClient, MCPClientConfig};

#[cfg(not(target_arch = "wasm32"))]
mcp_client: Option<MCPClient>,
```

**6. package.json** - Multi-target exports:
```json
"exports": {
  ".": {
    "import": "./pkg/bundler/agentic_jujutsu.js",
    "require": "./pkg/node/agentic_jujutsu.js",
    "browser": "./pkg/web/agentic_jujutsu.js",
    "deno": "./pkg/deno/agentic_jujutsu.ts"
  }
}
```

---

## Current Status

### ✅ What Works (v0.1.1)

- ✅ Native Rust builds (cargo)
- ✅ CLI tool (`jj-agent-hook`)
- ✅ crates.io publication (v0.1.0)
- ✅ All 70 library tests passing (native)
- ✅ MCP integration (native only)
- ✅ AgentDB sync (native only)
- ✅ **WASM builds (web, node, bundler, deno) - NEW!**
- ✅ **TypeScript definitions generated - NEW!**
- ✅ **Multi-target npm package ready - NEW!**

### ⏳ In Progress

- ⏳ npm publication (blocked on v0.1.1 release)
- ⏳ Integration tests (need fixture updates)
- ⏳ Version bump to 0.1.1

---

## Version Timeline

### v0.1.0 (Released - Nov 9, 2025)
- ✅ crates.io publication: https://crates.io/crates/agentic-jujutsu
- ✅ Native Rust support (all features)
- ✅ MCP integration (native only)
- ✅ 70/70 library tests passing
- ❌ WASM builds failed (errno dependency issue)

### v0.1.1 (In Progress - Nov 9, 2025)
- ✅ **WASM build issues FIXED**
- ✅ Conditional compilation implemented
- ✅ tokio/async-process excluded from WASM
- ✅ All 4 targets building (90KB each)
- ✅ TypeScript definitions generated
- ⏳ npm publication (pending version bump)
- ⏳ Integration test fixes
- ⏳ Documentation updates

### v0.2.0 (Future - 2-4 weeks)
- MCP support in WASM (via HTTP/WebSocket)
- Enhanced WASM functionality
- Performance optimizations
- Additional usage examples
- Production case studies

---

## Testing WASM Locally

### Build All Targets

```bash
# Build for all WASM targets (web, node, bundler, deno)
./scripts/wasm-pack-build.sh --release
```

### Test in Node.js

```bash
cd pkg/node
node -e "const jj = require('./agentic_jujutsu'); console.log('WASM module loaded!');"
```

### Test in Browser

Create a simple HTML file:
```html
<!DOCTYPE html>
<html>
<head>
  <title>agentic-jujutsu WASM Test</title>
</head>
<body>
  <script type="module">
    import init from './pkg/web/agentic_jujutsu.js';
    await init();
    console.log('WASM initialized!');
  </script>
</body>
</html>
```

### Test with Deno

```bash
cd pkg/deno
deno run --allow-all <<'EOF'
import * as jj from './agentic_jujutsu.ts';
console.log('Deno WASM module loaded!');
EOF
```

---

## Technical Notes

### Why WASM Simulation?

The WASM builds use **simulated jj commands** because:
1. **No native process execution** - WASM cannot spawn system processes
2. **Browser compatibility** - Must work in browser environments
3. **Deno/Node.js** - Could use real jj, but consistency across targets is important

### MCP in WASM (Future - v0.2.0)

MCP is currently **native-only** due to reqwest dependency. Future WASM support will use:
- **HTTP/fetch API** for browser
- **WebSocket** for real-time communication
- **Node.js http module** for Node.js target

---

## Status Updates

**2025-11-09 23:35 UTC:** ✅ WASM builds **FIXED AND WORKING**
- All 4 targets building successfully (90KB each)
- Conditional compilation implemented
- errno/tokio dependency issues resolved
- Ready for npm publication (pending v0.1.1 bump)

---

**Reported by:** Claude Code
**Tracked in:** GitHub Issues
**Fix scheduled for:** v0.1.1

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

Co-Authored-By: Claude <noreply@anthropic.com>