- Added extensive TypeScript enhancements: more schema‑related types, missing error types, reply status code typing via type providers, and moved router options to a dedicated key.
- Improved performance and stability: async resource binding for content‑type parsing, preparation for Promise.withResolvers, abort‑signal handling in listen, OPTIONS content‑type handling, and numerous test flakiness and EPIPE fetch error...
- Updated documentation (SECURITY.md, ecosystem plugins, multilingual, permissions, Hey API) and performed extensive internal clean‑ups and dependency bumps.
v5.5.0
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Fix for two Fastify security advisories (GHSA‑w2qp‑rph6‑63g4 and GHSA‑3m5p‑2c4r‑xxw2).
Added per‑route logging for Google Cloud Functions and introduced `Reply.prototype.mediaType` for easier content‑type handling.
Fixed trailer state clearing when removing all trailers and corrected requestCompleted handling to use null instead of undefined.