Structured, namespaced, TypeScript-first logging with beautiful terminal output and flexible transports
Works everywhere — styled badges in DevTools, pretty ANSI in the terminal, NDJSON in CI. Worker transport (Web Worker in browsers, worker_threads in Node.js) keeps the main thread free. No other structured logger offers this.
Organize logs by feature with namespaces. Create child loggers that inherit config and automatically attach request IDs, user context, and more.
Structured JSON schema with numeric log levels. trace=10, debug=20, info=30, warn=40, error=50, fatal=60. Compatible with Datadog, Loki, and any log aggregator.
Full date+time by default. ISO 8601, epoch seconds/ms, time-only, or custom functions. High-resolution nanosecond precision. Change format at runtime in the browser.
Mask sensitive data (passwords, tokens, PII) with redact: ['password', 'req.headers.authorization']. Applied before any output, transport, or buffer — nothing leaks. Children inherit parent paths.
Ship logs to any destination — HTTP endpoints, log files, writable streams, or the console. Batching, retry, and filtering built in.
Circular buffer stores logs for browser DevTools inspection. In Node.js, buffer is off by default for maximum throughput. Worker offloads transport processing from the main thread on both platforms.
Built with TypeScript from the ground up. Full type safety, zero runtime dependencies.
~10 KB gzipped, zero dependencies. On par with Pino on overhead, faster on JSON serialization, and significantly faster than Winston and Bunyan.