Changelog

Release notes for bourse. The full task-by-task development history lives in CHANGELOG-ARCHIVE.md; upcoming work is tracked in ROADMAP.md.

Unreleased

First hex.pm release as bourse, succeeding the retired ccxt_client package.

Ten provider-authored venue integrations — alpaca, binance, binancecoinm, binanceusdm, bybit, deribit, derive, hyperliquid, lighter, okx — each generated at compile time from one complete owned JSON spec. Runtime support is a closed set: constructing any other exchange fails with unsupported_exchange.
Two API surfaces. Raw per-exchange endpoint functions pass exchange responses through unchanged with signing, rate limiting, circuit breaking, and transport handled. The unified Bourse API adds 241 cross-exchange methods returning normalized structs, with bang variants and machine-readable descriptions.
Signing for every supported venue, including first-party signers for the three DEX venues: EIP-712 for Derive, msgpack action hashing for Hyperliquid, and a zk-Schnorr Port helper for Lighter. Bourse.Signing dispatches the authored recipes; no signing behavior is inferred at runtime.
WebSocket support via Bourse.WS — a thin wrapper over zen_websocket driven by authored per-exchange subscription and auth patterns.
Discovery and agent integration: Bourse.describe/0-2 for method signatures, parameters, errors, and return shapes, plus Bourse.MCP.tools/0 for MCP tool autodiscovery.
Operational layers: per-credential weighted rate limiting with response-header feedback, per-exchange circuit breakers, telemetry events, and sandbox resolution for all ten venues via Bourse.Exchange.new/2.

Renamed from ccxt_client to bourse, with the CCXT.* namespace becoming Bourse.*. See the migration notes in the README.
Interpretive judgment moved out of the runtime and into the authored specs. The heuristic signing classifier, symbol pattern inference, and long-tail fallback are removed; the runtime reads authored fields instead of guessing.
Correctness is verified against recorded venue reality — registered response recordings, accepted-request goldens, and recorded exchange errors — rather than against third-party client behavior.

Alpaca fetch_ohlcv/3-4 had no working call shape: the default path returned an empty list, failing silently as success, and the documented since option produced an HTTP 400. The authored request slice now emits a real dated window.

The published package carries the library and the ten authored specs. The repo-internal authoring and audit tooling is not shipped; mix ccxt.build_lighter_signer, the prerequisite for private Lighter calls, is the one task consumers receive.