fyeo

Open-source, self-hosted feature flag and remote configuration platform for Next.js. Think of it as a lightweight alternative to LaunchDarkly that runs inside your app with SQLite — no external services.

To add fyeo to an existing Next.js app, follow the step-by-step Getting started section on the Overview page at /overview (after you’ve integrated the app: copy the fyeo folders, install deps, and wire the root layout).

Quick start

1. Install

   npm install

2. Configure

   • Copy .env.example to .env.local (or set FYEO_SECRET and optionally FYEO_ENV).
   • The database is created at .fyeo/flags.db on first use.

3. Run

   npm run dev

4. Dashboard

   • Open http://localhost:3000/flags to manage flags.

Usage

• Server components / API

  import { getFlag, getAllFlags } from "@/lib/fyeo";
  const on = getFlag<boolean>("new-checkout-flow");
  const flags = await getAllFlags({ id: user.id });

• Client components

  • Wrap your app (or layout) with <FyeoProvider flags={flags}> and pass flags from getAllFlags() in the root layout.
  • Then: const on = useFlag("new-checkout-flow");

• Middleware (Edge)

  import { getFlagInMiddleware } from "@/lib/fyeo";
  const enabled = await getFlagInMiddleware("my-flag", request);

Environment variables

Variable	Description
FYEO_SECRET	Secret for protecting admin API
FYEO_ENV	Current environment slug (default: development)
FYEO_DB_PATH	DB path (default: .fyeo/flags.db)

Project layout

• lib/fyeo/ — DB, evaluator, SDK, types
• app/api/fyeo/[...path]/ — REST API
• app/(dashboard)/ — Admin UI (Overview, Flags, Environments, Audit) at top-level routes