GCP

Host your cluster in your GCP project: Postgres and the runners run on Compute Engine instances in a VPC of their own. A regional load balancer on a static address serves the pool’s gateway, so a Cloud Run service, a Worker or anything else calls the rooms by id.

src/Cluster.ts

import * as ClusterGCP from "@alchemy.run/effect-cluster/GCP";
import * as Layer from "effect/Layer";

export const Database = ClusterGCP.Database("Cluster");

export const Default = ClusterGCP.ComputeEnginePool("Default", { replicas: 2 }).pipe(
  Layer.provide(Database),
);

Install @alchemy.run/gcp and finish GCP setup.

GCP projectyour profile's project

load balancerstatic address

programCloud Storage bucket

VPCand its subnetwork

DatabaseCompute Engine instance

disk

persistent

DefaultComputeEnginePool

instancezone a

instancezone b

Firewall rules let only the runners, by network tag, reach Postgres and each other. Each runner fetches the pool's program from the bucket.

The database

ClusterGCP.Database creates a VPC and subnetwork, and runs Postgres in a container on an instance with a persistent disk of its own. Firewall rules let only the runners reach it, by network tag, and let runners reach each other.

src/Cluster.ts

import * as ClusterGCP from "@alchemy.run/effect-cluster/GCP";

export const Database = ClusterGCP.Database("Cluster", {
  machineType: "e2-standard-2",
  diskSize: 100,
});

The pool

ComputeEnginePool runs one instance per runner, spread across the region’s zones. Each fetches the pool’s program from a Cloud Storage bucket and runs it on the host network; a change to the program reaches every runner through its metadata.

src/Cluster.ts

import * as ClusterGCP from "@alchemy.run/effect-cluster/GCP";
import * as Layer from "effect/Layer";

export const Database = ClusterGCP.Database("Cluster");

export const Default = ClusterGCP.ComputeEnginePool("Default", {
  replicas: 3,
  machineType: "e2-standard-2",
}).pipe(Layer.provide(Database));

Cloud Run can’t run runners: runners take connections from each other, and Cloud Run instances can’t.

Call it from Cloud Run

src/Api.ts

import * as GCP from "@alchemy.run/gcp";
import * as Effect from "effect/Effect";
import * as HttpServerResponse from "effect/http/HttpServerResponse";
import { Room } from "./Room.ts";

export default class Api extends GCP.Run.Service<Api>()(
  "Api",
  { main: import.meta.url, invokerIamDisabled: true },
  Effect.gen(function* () {
    const rooms = yield* Room;
    return {
      fetch: Effect.gen(function* () {
        const lobby = yield* rooms.getByName("lobby");
        return yield* HttpServerResponse.json({ members: yield* lobby.Join({ name: "sam" }) });
      }).pipe(Effect.orDie),
    };
  }),
) {}

Every option, with its default, is in the reference: Database and ComputeEnginePool.