Changelog

All notable changes to this monorepo are recorded here. Releases for each package follow Semantic Versioning; the entries below are grouped by version-date so cross-package changes that ship together stay readable.

The format is loosely based on Keep a Changelog.

2026-06-22 — 0.2.1

@mqttkit/[email protected]

Added — @mqttkit/core 0.2.1

• MQTT 5 shared subscriptions ($share/<group>/<filter>). parseSharedSubscription() follows §4.8.2; canSubscribe() strips the prefix before route matching and exposes shared.group to the subscribe policy. Lets you deploy multiple consumer instances behind one broker without custom load-balancing.
• Per-route timeout and concurrency. topic({ timeout, concurrency }) guards handler execution. Timeout surfaces as phase: 'timeout'; concurrency rejection surfaces as phase: 'overload'. Inflight count is tracked on the route for use by metrics and graceful shutdown.
• app.onMetric(handler). Emits a structured MqttMetricEvent once per dispatch and once per publish — { type, topic, route?, durationMs, result, errorPhase? }. Designed to feed Prometheus / OpenTelemetry / statsd without middleware around every route.
• Graceful shutdown. app.stop({ drain: true, timeout: 30_000 }) is now the default behaviour: the dispatcher refuses new inbound dispatches, polls every route's inflight count to zero (or until the timeout), then runs onStop hooks, cancels in-flight RPC, and stops the broker adapter. app.activeCount() reports the current sum of in-flight handlers for health checks. Pass { drain: false } for the legacy immediate shutdown.
• MQTT 5 user properties on ctx. ctx.userProperties exposes inbound packet.properties.userProperties as a flat read view, so middleware can extract traceparent, correlation IDs, or any side-band metadata without touching adapter-specific packet shape.
• Outbound publish hooks. app.onBeforePublish(hook) runs immediately before every outbound publish (both app.publish() and ctx.publish() / ctx.reply() / app.request(), which all funnel through the same path). Hooks receive a mutable { topic, payload, options } view and can mutate options — typical use is merging traceparent into options.properties.userProperties so OTel context propagates across brokers. A throw aborts the publish and surfaces through onError with phase: 'publish'.
• Raw payload on onError. MqttErrorPayload.payload carries the raw buffer for inbound phases (validation / policy / middleware / handler / timeout / overload) and the original MqttPayload for publish. Lets exporters (Sentry, structured logs) capture the offending message body, not just the topic.
• New docs pages under the Production section: Shared Subscriptions, Handler Timeout & Concurrency, Metrics, Graceful Shutdown, Tracing & User Properties (with full OpenTelemetry wiring example).

2026-06-22 — 0.2.0

@mqttkit/[email protected], @mqttkit/[email protected], @mqttkit/[email protected], @mqttkit/[email protected] (initial), @mqttkit/[email protected] (initial).

Added — @mqttkit/core 0.2.0

• Schema validation. topic({ schema }) accepts any Standard Schema v1 validator (zod ≥3.24, valibot ≥1, arktype, …). Validated output is exposed on ctx.body with full type inference. validate option controls direction ('inbound' | 'outbound' | 'both' | false).
• SchemaProvider extension point. app.addSchemaProvider(provider) lets non-Standard-Schema libraries (e.g. raw TypeBox) plug in without core depending on them. MqttkitInferExtensions<T> provides type-only registration for ctx.body inference.
• RPC. app.request(topic, payload, options?) sends a request using MQTT 5 responseTopic + correlationData and resolves on reply. ctx.reply(payload) answers on the device side.
• Error lifecycle. app.onError(handler) and per-route onError receive a structured { error, topic, phase, route, ctx } payload. phase is one of middleware | handler | validation | policy | publish. Validation failures emit a SchemaValidationError and skip onMessage.
• Testing entry. New @mqttkit/core/testing sub-export ships createTestApp() and an in-memory TestBroker with dispatch() / onPublish hooks. Lets apps be unit-tested without spawning aedes.
• Pattern module. Topic-pattern matching extracted into pattern.ts and exported from the package root.

Added — @mqttkit/aedes 0.2.0

• Forwards MQTT 5 publish properties (responseTopic, correlationData, contentType, messageExpiryInterval, userProperties, payloadFormatIndicator) when calling broker.publish. Required for app.request() RPC round-trips.
• Bumps @mqttkit/core peer to ^0.2.0.

Added — @mqttkit/asyncapi 0.2.0

• resolvePayloadSchema(): route schemas that implement Standard Schema are now reduced to a JSON Schema for the generated document. Order:
  1. raw JSON Schema object — used as-is
  2. Standard Schema with ~jsonSchema attached — uses the attached schema
  3. fallback: { description: 'Validated by <vendor>' }
• Lets @mqttkit/zod's jsonify() (and TypeBox's native JSON Schema layout) flow into the AsyncAPI document.
• Bumps @mqttkit/core peer to ^0.2.0.

Added — @mqttkit/typebox 0.1.0 (initial)

• typeboxProvider: register with app.addSchemaProvider(typeboxProvider) and pass raw Type.X(...) schemas directly to topic({ schema }). TypeBox schemas detected by the Kind symbol and validated via @sinclair/typebox/value.
• Type-only module augmentation so ctx.body is inferred via Static<T>.
• TypeBox schemas are JSON Schema natively, so @mqttkit/asyncapi outputs the full payload automatically.

Added — @mqttkit/zod 0.1.0 (initial)

• jsonify(schema, options?): attaches a JSON Schema representation under ~jsonSchema and returns the same zod instance. Closes the gap where @mqttkit/asyncapi falls back to Validated by zod because zod 3.x doesn't expose JSON Schema by default.
• zod ≥3.24 already implements Standard Schema, so runtime validation works without jsonify — this helper is only needed when emitting AsyncAPI docs.

Examples

• New examples/schema-validation with zod, typebox, coexist, and manual variants.
• New examples/rpc demonstrating app.request() / ctx.reply().
• examples/asyncapi-docs now defaults to the TypeBox variant; added a dev:zod script that shows zod + jsonify flowing into the AsyncAPI document.

Internal

• Root tsconfig.json excludes **/dist/** to avoid a parallel-build race where one package's tsup pass discovered another package's mid-clean dist.

2026-XX-XX — initial release

@mqttkit/[email protected], @mqttkit/[email protected], @mqttkit/[email protected].

Initial publish of the framework: ordered middleware, topic router, typed context with decorate() service injection, broker lifecycle events, app.publish() for service-side push, Aedes TCP + MQTT-over-WebSocket adapter, and the AsyncAPI 3.0 documentation plugin.