Pattern-matching microservices for Node.js. Register handlers under plain-object patterns, then call them in the same process or over TCP, Unix sockets, named pipes or RabbitMQ, with the same calling code.

// math.js
const devis = require("devis");
devis.push({ role: "math", cmd: "sum" }, async ({ left, right }) => left + right);
devis.listen({ host: "127.0.0.1", port: 3030 });

// client.js
const devis = require("devis");
devis.connect({ id: "math", host: "127.0.0.1", port: 3030 }, async () => {
    console.log(await devis.call({ role: "math", cmd: "sum" }, { left: 1, right: 2 })); // 3
    devis.close();
});

The client needs no service name: each service announces its patterns, and Devis routes every call to the one that matches best, in turn when several instances run. Since Devis 4.1: partial matching, automatic reconnection, load balancing and OpenTelemetry traces across services, on top of async handlers, timeouts, graceful shutdown and TypeScript types.

npm install devis   # Node.js 22 or later

Package	What it does
devis	The framework: patterns, local calls, TCP, Unix sockets, named pipes
devisPattern	The pattern matcher behind Devis
devis-mongo-client	MongoDB plugin
devis-pub_sub-redis	Redis pub/sub plugin
devis_rabbitmq	RabbitMQ transport with per-call RPC replies
generator-devis	yo devis: scaffold a gateway and a microservice

• Read the devis README for the API and recipes.
• Run the examples: local calls, TCP, MongoDB, Redis, RabbitMQ.
• Scaffold a project: npm install -g yo generator-devis && yo devis.

All packages are MIT licensed and tested on Node.js 22 and 24.