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SSSN

SSSN SSSN

sssn.one

SSSN is the protocol and service layer for semantic channels in PSI services. It carries typed events, artifacts, and snapshots between services, workers, robots, apps, and agents while keeping databases, brokers, feeds, object stores, graph stores, and local filesystems behind the stable Channel interface.

Channel Named semantic data interface with schema, form, description, and metadata.
Event Append-only record with payload, schema, source, and correlation metadata.
Artifact Larger payload stored separately and linked back to events.
Snapshot Latest materialized state for a name, channel, or derived view.

Fast Path

from sssn import Channel, Event, LocalStore

store = LocalStore(".sssn")
store.create_channel(Channel(name="events", schema="demo.schemas:Event"))
event = store.append_event(
    Event(channel="events", source="demo", kind="message", payload={"text": "hello"})
)

assert store.query_events("events")[0].id == event.id

The default local backend is intentionally boring:

.sssn/
  sssn.sqlite
  artifacts/

SQLite owns metadata and cursors. The filesystem owns artifact payload bytes. That simple backend gives tests, examples, demos, and local tools a stable semantic channel layer before anyone needs a broker or hosted service.

Shape

flowchart LR A["Producer service"] --> B["Channel"] B --> C["Events"] B --> D["Artifacts"] B --> E["Snapshots"] C --> F["Worker subscription"] F --> G["Derived event"] G --> B

SSSN is not observability. Observability systems explain how software behaves. SSSN defines the channel protocol and service surface for data that other systems consume: policy samples, robot state, analysis results, human annotations, and latest-state materializations.

What SSSN Owns

  • channel, event, artifact, snapshot, and subscription models,
  • local store semantics and cursor validation,
  • a portable HTTP service for store access,
  • sync and async HTTP clients,
  • PsiHub metadata helpers for channel and snapshot resources,
  • shared local config resolution for SSSN refs.

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