> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tracelit.io/llms.txt
> Use this file to discover all available pages before exploring further.

# v0.1.1 — Apr 27, 2026

> Node.js SDK v0.1.1 — Apr 27, 2026

# v0.1.1 — Apr 27, 2026

**New**

* `Tracelit.metrics.observableGauge()` — callback-based gauge that reads on export interval instead of on every call. Ideal for expensive computations like queue depth polling
* `WinstonTransport` — named export that bridges Winston logs to the OTel LoggerProvider with automatic `trace_id` / `span_id` injection
* `createPinoDestination()` — Pino multistream destination for forwarding logs to the Tracelit log pipeline
* `Tracelit.expressMetricsMiddleware()` — drop-in Express middleware that records `http.server.request.count`, `http.server.request.duration`, and `http.server.error.count` per route

**Improvements**

* `ErrorAlwaysOnSampler` + `ErrorSpanProcessor` pair now guarantees error span export even at `sampleRate: 0.0`
* Console bridge (`console.debug/log/info/warn/error`) now preserves original output — no silent swallowing
* `process.event_loop.lag` histogram timer switched to `unref()` so it never prevents process exit
* Dual CJS + ESM bundles with TypeScript 5 declaration files — no `moduleResolution` shenanigans needed

**Fixes**

* Fixed `Tracelit.metrics` returning stale `null` reference after `Tracelit.start()` called more than once
* Fixed ESM named exports (`WinstonTransport`, `createPinoDestination`) not resolving in some bundler setups