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Overview

The node adapter, flare.json config, and app.run() for long-lived Node.js servers.

AI generated, pending review Updated 10 days ago · Flare 0.3

Node.js is the default Flare target. The node adapter reads flare.json from the project root (with FLARE__* environment overrides), supports host.singleton() for process-lifetime services, and returns an app with run() for a long-lived HTTP and WebSocket server.

Minimal app

import { FlareHost, FlareResponse } from "@flare-ts/core";
import { node } from "@flare-ts/core/node";

const host = new FlareHost(node);

host.http.get("/health", () => new FlareResponse(200, { ok: true }));

const app = host.build();
app.run();

app.run() runs startup hooks, binds the server, and moves host.state to "ready" when the socket is listening. WebSocket upgrades on the same port are handled when you register host.ws routes.

Config

A missing flare.json on Node is logged, not fatal: defaults plus env fill in. See Configure your app and flare.json reference.

What Node supports

Feature	On Node
`host.singleton()`	Yes
`host.scoped()`	Yes
`host.ws` channels	Yes (process-wide broadcast domain)
`host.durableObject()`	No (Workers only)
Graceful shutdown	Yes via `NodeRunHandle.stop()`

Run and shutdown: ports, drain, SIGTERM
Lifecycle: host.state state machine
Install: Node version and packages