Nereus Delay is a Java 21 library and service core for durable delayed-message scheduling across Kafka and Pulsar destinations.
The implementation is built in small, testable layers:
protocol: canonical identities, source positions, hashing, and Shard Log framing;store: one RocksDB instance per Delay Shard with the seven registered application column families;runtime: deterministic command application and the embedded service used by conformance tests;scheduler: persistent Destination Lane scheduling and bounded weighted DRR;adapter: broker-specific ingress and destination boundaries.
The normative design is docs/Nereus Delay 设计.md.
Major design changes are proposed and reviewed through
docs/proposals/, then folded directly into that
single current design baseline.
Exact wire, key, enum, and stable-code values are in
docs/PROTOCOL-REGISTRY.md. The implementation
status and evidence matrix are maintained in
docs/IMPLEMENTATION-STATUS.md.
The role and authority order of the design, Registry, ADR, status, and audit
documents is summarized in docs/README.md.
The terminology glossary is CONTEXT.md; it explains the fixed
meaning of names such as deliverAt and Source Position without replacing the
normative design.
Run the build with an isolated Gradle cache when the host Gradle native cache is not writable:
GRADLE_USER_HOME=/private/tmp/nereus-delay-gradle ./gradlew clean check