howthFast JavaScript & TypeScript builds

A commodius vicus of recirculation for your JavaScript.

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Installation

GitHub

1.2ms Cold Transpile

Transpile TypeScript files cold in 1.2ms. Warm rebuilds in 0.1ms. 780x faster than tsc.

8.7x Faster Tests

Run 120 tests in 19ms. 8.7x faster than node --test, on par with bun. Warm Node worker pool with SWC transpilation.

Bundler with Tree Shaking

Dead code elimination, code splitting on dynamic imports, CSS bundling with minification, and a Rollup-compatible plugin system.

Dev Server + HMR

Built-in dev server with hot module replacement. See changes instantly during development.

SWC Backend

Uses SWC for transpilation. Rust-native, no Node.js overhead. Content-based caching with parallel file hashing.

Node.js Compatible

85% Node.js API coverage. Full support for http, fs, crypto, streams, and more. Run Express, Next.js, and SvelteKit.

Benchmarks

Transpile (Apple M3 Pro)

Tool	Cold	Warm	Peak RSS
howth	1.2ms	0.1ms	8.2MB
tsc --noEmit	975ms	-	143MB

Test Runner (15 files, 120 tests)

Tool	Median	p95	Peak RSS
howth	19ms	20ms	-
bun test	20ms	25ms	56.8MB
node --test	163ms	189ms	56.8MB

howth is 8.7x faster than node and 1.05x faster than bun.

Quick Start

# Install
curl -fsSL https://raw.githubusercontent.com/jschatz1/howth/main/install.sh | sh

# Build your project
howth build

# Watch mode
howth build --watch

# Bundle for production
howth bundle src/index.ts -o dist/bundle.js

# Dev server with HMR
howth dev src/index.ts --port 3000