Capabilities

@anvia/server has one public entry point and a deliberately small responsibility: encode an asynchronous event source and expose it through Fetch-compatible streaming primitives.

Capability	API	Behavior
Streaming response	createEventStream	Wraps any AsyncIterable<T> in a JSONL or SSE Response
UI response	createUIStreamResponse	Same transport behavior, typed for UIStreamEvent
JSONL encoder	createJsonlStream	Emits one serialized event plus newline per chunk
SSE encoder	createSseStream	Emits JSON data fields with optional event names and retry value
Resumable producer	createResumableStream	Persists numbered event records and yields resume envelopes
Resume consumer	resumeStreamEvents	Replays after a cursor and tails a running stream
Development store	createMemoryResumableStreamStore	Process-local resumable state for tests and local use
Store contract	ResumableStreamStore	Application-defined durable/shared persistence boundary

What the package adds

Response helpers set transport defaults unless the application already supplied them:

• Cache-Control: no-cache, no-transform
• Connection: keep-alive
• X-Accel-Buffering: no
• JSONL or SSE Content-Type

Encoder failures become a final { type: 'error', error } event. Native Error values retain name and message but not their stack.

What it does not add

Server does not own model execution, cancellation policy, authorization, CORS, CSRF protection, compression, durable storage, reconnecting clients, or background-job lifecycle. A deployment can still buffer or terminate streams despite the response headers.

See the API reference for all option and envelope types.