# Changelog

## v2.2.0 — 2026-08-22

The collector this library emitted to no longer exists, and the record format it
emits is now specified rather than merely implemented. `libtrace` itself is
unchanged: it is, and always was, a client that writes records to an
`AF_UNIX` `SOCK_DGRAM` socket and holds no database.

- The `traced` collector daemon was retired: it had no emitters and no consumers
  left. Its systemd unit, its configuration and its tooling are gone. Anything
  built against `libtrace` is unaffected — the socket it writes to is the
  contract, not the process on the other end.
- **`docs/TRACE_SPEC.md` §4 is now normative.** With no collector distributed,
  the record format is what a third party implements a collector against, so it
  is stated rather than left to be read out of an implementation.
- Corrected the description of this library. It was called "SQLite-backed" in
  places; that described the collector, never this code. Services never touch a
  database.
- Removed the Claude Code introspection hooks: deleted `hooks/claude-trace-hook`
  and the settings wiring that invoked it — the inverse of TRACE-04. Internal
  tooling only; never part of the MIT library release (v2.1.0 was
  library-only). The `trace-emit` CLI and `libtrace` are unaffected.

## v2.1.0 — 2026-04-03

Open-source release under MIT license (library only).

- MIT license
- SPDX-License-Identifier headers in library source files
- 78 unit tests (lifecycle, emit, Span, log, trace ID, thread safety)
- README, CONTRIBUTING.md, CHANGELOG

## v2.0.0 — 2026-03-20

Complete v2 rewrite. Daemon-based architecture.

- Span (RAII scoped timer) with entry/exit events and measured duration
- Point events via emit()
- Structured logging to stderr + collector
- Unix datagram socket transport (fire-and-forget)
- Trace ID generation for cross-process correlation
- Graceful degradation when collector is unavailable

## Pre-release History

| Date | Change |
|------|--------|
| 2026-03-20 | T-03: Trace v2 daemon refactor (Phases 1-4). |
| 2026-03-18 | TRACE-05: Relay support (workstation → collector host). |
| 2026-03-18 | TRACE-04: Claude Code hooks + trace-emit CLI. |
| 2026-03-17 | TRACE-03: traced self-trace + config file. |