feature-flags

name	feature-flags
description	Feature flags patterns including LaunchDarkly, Statsig, Vercel Edge Config, environment-based toggles, gradual rollouts, and user targeting
layer	utility
category	backend
triggers	["feature flag","feature toggle","LaunchDarkly","Statsig","Edge Config flags","gradual rollout","canary release","user targeting","A/B test flag"]
inputs	["feature name","rollout strategy","targeting rules","flag provider"]
outputs	["flag implementation","targeting config","rollout plan","cleanup checklist"]
linksTo	["vercel","monitoring","cicd"]
linkedFrom	["ship","optimize","cook"]
preferredNextSkills	["monitoring","cicd"]
fallbackSkills	["vercel","env-vars"]
riskLevel	low
memoryReadPolicy	selective
memoryWritePolicy	none
sideEffects	["May add SDK dependency (LaunchDarkly, Statsig, @vercel/edge-config)","May modify middleware or layout for provider wrappers"]

Feature Flags Skill

Purpose

Feature flags decouple deployment from release. Ship code to production behind flags, then control visibility through configuration rather than code changes. This skill covers provider-based and DIY flag systems with safe rollout patterns.

Key Patterns

Strategy Comparison

Approach	Best For	Latency	Cost
Environment variables	Simple on/off per environment	Zero	Free
Vercel Edge Config	Edge-fast reads, small flag sets	~1ms	Free tier available
LaunchDarkly	Enterprise targeting, analytics	~20ms	Paid
Statsig	A/B testing + flags combined	~15ms	Free tier available
Database flags	Custom rules, full ownership	Varies	Self-hosted

Environment-Based Toggles (Simplest)

// lib/flags.ts — zero-dependency flags
const flags = {
  newCheckout: process.env.NEXT_PUBLIC_FLAG_NEW_CHECKOUT === "true",
  betaDashboard: process.env.FLAG_BETA_DASHBOARD === "true",
} as const;

export type Flag = keyof typeof flags;
export function isEnabled(flag: Flag): boolean {
  return flags[flag];
}

// Usage in component
 (()) {
   ;
}