Feature Flag is a toggle in code that enables/disables functionality without deploying new code.
Feature flags (LaunchDarkly, Flagsmith, Statsig, GrowthBook, PostHog) decouple deploy from release. Enable: gradual rollouts, A/B testing, kill switches, beta testing per user. By 2026, feature flag platforms include built-in experimentation and analytics. Best practice: limit flags to <90 days lifespan to prevent technical debt.
Feature flags decouple deploy from release. You can ship code dark, test it in production, and turn it on for users only when it is ready — radically reducing the risk of any individual change.
A team merges new checkout code behind a feature flag, deploys it to production, and turns it on for 1% of users first. They monitor errors, raise the rollout to 10%, then 100% — or roll back instantly if something looks wrong.
Feature flags are not just for big launches. Even small changes benefit from being deployable but switchable, especially in services where rollback would otherwise require a full redeploy.
Treat flags as code: name them clearly, give them owners and expiry dates; orphaned flags accumulate into a separate kind of technical debt.
Feature Flag falls under the Hosting category.
These tools put feature flag into practice. Compare features, pricing, and ratings:
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