Early draft:
1) REST API and change propagation## Core: REST API build-out, documentation & distribution
- Support apps and the API-driven frontend effort with cacheable high-traffic entry points and clean content interfaces.
- Expand mediawiki-containers environment to fully support RESTBase, and improve support for development use cases.
## Focus: EventBus & change propagation
- Introduce general resource change topic: T126687
2) API on the edge: Lower the latency for hot API end points by providing them directly on the edge, using data replicated from the main DCs- Process subscriptions on this topic from the change propagation service.
3) Depending on results of evaluation in Q3- Replace RESTBaseUpdate extension.
## Experiment: Streaming content composition in ServiceWorkers & node.js
- Prototype a streaming page composition solution running in ServiceWorkers (Chrome 50+) and node.js, replace ExternalStore for wikitext storagegeneralizing a prototype [by Jake Archibald](https://jakearchibald.com/2016/streams-ftw/).