OpenPhase Labs builds open infrastructure for the public agencies that operate physical systems - starting with traffic signals.

Our work is published as open contracts first, implementations second. A contract here is a schema, not an application - it does nothing by itself, and that is the point: anyone can build against it without building with us.

Our transportation line: software for the agencies that operate traffic signals.

Two of them, and they are not the same thing. Both are Protobuf; they sit on different boundaries.

OpenPhase - the messages Traffic Ops products speak to each other, over NATS JetStream, MQTT and other transports. Publish/subscribe, product to product. Protobuf schemas plus a spec doc per subject.

TSIGMA plugin contract - the boundary between a TSIGMA host and the plugins it loads: decoders, ingestion methods, reports, notifications, auth and storage. gRPC over a subprocess plugin protocol, with a host-served callback plane. Host to plugin, not product to product.

If you are integrating two systems, you want OpenPhase. If you are writing a plugin for TSIGMA, you want the plugin contract.

TSIGMA (not yet published) - automated traffic signal performance measures. Ingests controller event logs, decodes them, validates them, and reports on them. Extended through plugins rather than forks, against the contract above.

Contracts are published under MPL-2.0: modifications to the contract files stay open, so a divergent copy cannot be closed, while anything built against them is yours.