Foundations & the system
Cloud-native principles and the building blocks: communications, composition, data, events, streams.
Cloud-Native Principles
Cloud-native as a set of runtime properties, not a stack of tools — the six pillars, leaning on the platform, design-first contracts, and the twelve-factor app reframed by who owns each factor.
Communications
Four interaction styles and four defaults — REST at the edge, gRPC for internal calls, GraphQL for composed reads, async events for facts — and pushing resilience onto the mesh instead of into your code.
Composition
Composing many back-ends behind one schema without coupling them — a GraphQL gateway that fans out to REST and gRPC, the resolver that makes it concrete, and the three places aggregation belongs.
Data
Read/write model separation, change data capture, and the transactional outbox that makes 'save the state and publish the event' a single atomic act.
Event-Driven
Decoupled facts that fan out — the event backbone, producing and consuming with commit-after-side-effect, schemas as the enforced contract, and the difference between event sourcing and event streaming.
Stream Processing
Deriving new streams from streams — stateful, changelog-backed windowed aggregation, and KEDA scaling workers on consumer lag rather than CPU, down to zero when the topic is quiet.