Elysia is a fast and type-safe web framework for Bun. RivetKit integrates seamlessly with Elysia using the .mount() method.

View Example on GitHub

Check out the complete example

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Installation

Install Elysia alongside RivetKit:

npm install elysia
# or with bun
bun add elysia

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Basic Setup

1

Create Your Registry

Set up your Rivet Actors:

// registry.ts
import { actor, setup } from "@rivetkit/actor";

export const counter = actor({
  state: { count: 0 },
  actions: {
    increment: (c, amount: number = 1) => {
      c.state.count += amount;
      c.broadcast("countChanged", c.state.count);
      return c.state.count;
    },
    getCount: (c) => c.state.count,
  },
});

export const registry = setup({
  use: { counter },
});
2

Integrate with Elysia

Mount RivetKit into your Elysia application:

// server.ts
import { registry } from "./registry";
import { Elysia } from "elysia";

const { client, handler } = registry.createServer();

// Setup Elysia app
const app = new Elysia()
  // Mount RivetKit handler
  .mount("/registry", handler)
  // Add your API routes
  .post("/increment/:name", async ({ params }) => {
    const name = params.name;
    
    const counter = client.counter.getOrCreate([name]);
    const newCount = await counter.increment(1);
    
    return `New Count: ${newCount}`;
  })
  .get("/count/:name", async ({ params }) => {
    const name = params.name;
    
    const counter = client.counter.getOrCreate([name]);
    const count = await counter.getCount();
    
    return { count };
  })
  .listen(8080);

console.log("Server running at http://localhost:8080");