mercury

A Rust port of mercury-composable — Accenture's event-driven, composable application platform (the Java engine is the canonical reference; both engines release in lock-step at the same version), carrying the same vision: build applications from small, fully-decoupled functions wired by route name, orchestrated as configuration, and modeled as an executable knowledge graph.

Status: all three layers ported and milestone-closed across 96 verified increments; full workspace test suite, clippy and fmt clean; benchmarked (RPC ~155K ops/s @ 6μs). The AI-agent documentation is battle-tested — twelve consecutive fresh-agent exercises passed with zero documentation lookups, across both engines. See CHANGELOG.md and docs/INCREMENTS.md.

Each layer builds on the one below (foundation → UI):

1. platform-core — the actor-model event bus: route-addressed functions coupled only by route name + an immutable EventEnvelope, over a tokio async runtime. Plus the operable runtime: REST automation (rest.yaml is the router, on hyper), actuators, tracing + correlation-id, an async HTTP client, and a WebSocket server.
2. event-script — composable orchestration: a YAML flow DSL that choreographs functions into transactions (sequential / decision / parallel + fork-join / pipelines / sub-flows), with data mapping, resilience, and an HTTP flow adapter. No orchestration in code.
3. active knowledge graph — the semantic layer: MiniGraph property graphs whose nodes carry executable skills, so traversing the graph is running the application — with the browser-based MiniGraph Playground for building, running and inspecting graphs.

The seven library crates publish under mercury-prefixed package names, while the lib (code-facing) names stay short — Cargo.toml and code look like:

[dependencies]
mercury-platform-core = "4.12" # code: use platform_core::...
mercury-event-script = "4.12" # code: use event_script::...
mercury-knowledge-graph = "4.12" # code: use knowledge_graph::...

(The macro crates are pulled in automatically; add mercury-minigraph-state-redis for the Redis suspend/resume state store.)

Rust (stable) + Cargo. Run any example:

cargo run -p hello-world # layer 1 — event bus + HTTP
cargo run -p hello-flow # layer 2 — a YAML flow over HTTP (port 8100)
cargo run -p minigraph-playground # layer 3 — the Playground; open http://127.0.0.1:8085/

Verify the workspace:

cargo test --workspace
cargo clippy --workspace --all-targets
cargo fmt --all --check

The human developer guide is a 20-page MkDocs site under docs/ (Getting Started, per-layer guides, references, port scope) — published at https://accenture.github.io/mercury/ , or build it locally with mkdocs serve. AI agents start at docs/llms.txt: the machine-readable map of the AI-agent documentation that the fresh-agent validation sweep was driven from.

The Kafka service mesh (service discovery + sync-over-Kafka, the connectors/ tree) and Spring (rest-spring-3/-4) are out of scope. minimalist-kafka and twin-kafka are lightweight cloud-native connectors — not part of the mesh exclusion — planned for future iterations together with sync-over-async (see docs/background/port-scope.md). graph.js is deliberately retired in this port (an arbitrary-code interpreter is an attack surface); graph.math and graph.task cover its use cases.

This repository previously hosted the original Java implementation of Mercury (up to v3.0.19); it was repurposed as the home of the Rust version on 2026年07月20日. Versions 1.13.0 and 2.1.0–2.7.0 remain available as release branches in this repository. All known field installations have been upgraded to version 4.x using the mercury-composable repo — the canonical Java implementation this port follows.

See CONTRIBUTING.md and CODE_OF_CONDUCT.md. Licensed under the Apache License 2.0.