Open Source · MIT License

Feature flags for vibes

No server. No config. No build step. Just add <script> tag in your <head> and start benefiting from feature flags.

Built for AI agents and vibe coders.

~11KBgzipped
Minimaldependencies
MITlicense
Withoutbackend
index.html
<script type="module" src="https://unpkg.com/@vibe-flags/core"></script>

<!-- Toggle flag -->
<vibe-flags-boolean name="showBanner" value="false">
  <div>Welcome to the beta!</div>
</vibe-flags-boolean>

<!-- Multiple options flag -->
<vibe-flags-select name="theme">
  <vibe-flags-option value="light">...</vibe-flags-option>
  <vibe-flags-option value="dark">...</vibe-flags-option>
</vibe-flags-select>

<!-- Beautiful toolbar -->
<vibe-flags-toolbar></vibe-flags-toolbar>

How it works

Up and running in 30 seconds

No CLI, no framework, no signup. Three simple steps and you have feature flags up and running.

01

Add the script tag

Drop one line into your HTML. The library self-registers all custom elements automatically.

<script
  type="module"
  src="https://unpkg.com/
    @vibe-flags/core">
</script>
02

Declare your flags

Wrap content in flag components. Boolean for toggles, select for variants. No JavaScript needed.

<vibe-flags-boolean
  name="isVip"
  value="false">
  <p>Welcome, VIP!</p>
</vibe-flags-boolean>
03

Toggle from the toolbar

Add the toolbar anywhere. It auto-discovers all flags and persists state to localStorage.

<vibe-flags-toolbar
  position="bottom-right">
</vibe-flags-toolbar>

Features

Everything you need

A complete feature flag solution that works out of the box.

No Login Required

Pure localStorage. No accounts, no API keys, no servers.

Any Framework

Web components work in React, Vue, Svelte, Angular, or plain HTML.

~11KB Gzipped

Tiny footprint. Zero runtime dependencies. Zero performance impact.

Persistent State

Flag values survive page refreshes and stay in sync across tabs.

TypeScript Native

Full type safety, imperative store API, and a reactive event system.

Polished Toolbar

Draggable FAB, resizable panel, toggles and dropdowns. Dark and light.

AI-native

Built for humans & AI agents

Flags are declared in plain HTML. LLMs and AI coding agents can read, write, and toggle them without learning any SDK.

PromptCopy and paste into your AI assistant
Design 5 distinctly unique and visually different variations of a section of my website. Use your best designer skills to make each variant professional, modern, and creative — vary the layout, typography, colors, spacing, and visual style across all 5. Use Vibe Flags (https://vibe-flags.appwrite.network/llms-full.txt) to let me switch between variants in its toolbar, so I can pick the one I like most.

Section to redesign: [EXPLAIN YOUR SECTION HERE]

URL overrides

Share exact flag states via URL

Override any flag with a query parameter — no localStorage changes. Perfect for QA snapshots, review links, or demo states.

  • URL params take priority over localStorage
  • Ephemeral — not saved on page load
  • Works for both boolean and select flags
browser address bar
https://yourapp.com
  ?vf:darkMode=true
  &vf:theme=dark
  &vf:showBanner=false

Comparison

vs. the enterprise alternatives

LaunchDarkly and friends are great for production at scale. Vibe Flags is for prototyping, vibe-coding, and AI-assisted development.

FeatureVibe Flags
Zero config setup
Backendless / offline
No account needed
localStorage persistence
AI-friendly HTML API
Free & unlimited
Bundle size~11KB
Targeting rules
Audit trail

Start shipping faster

One script tag. Feature flags, variant switching, and a polished toolbar — no backend, no account, no config.

index.html
<script
  type="module"
  src="https://unpkg.com/@vibe-flags/core">
</script>