Ship code, not risk
Everything about feature flags, in plain words.
Guides, real use cases and news about feature flags: how to roll out safely, switch off what breaks, run experiments and clean up the flags you no longer need.
Guides
How feature flags work, from the first toggle to progressive delivery at scale.
Use cases
Real situations where a flag saves a release: kill switches, betas, migrations and more.
Latest articles
- Guides3 min read
Percentage rollouts: how feature flags keep a user in the same group
How a feature flag turns a feature on for exactly 10% of users, and keeps each user in their group as you go to 50% and 100%. With TypeScript code.
- Use cases3 min read
Stale feature flags: how to find them and remove them safely
Old feature flags turn into dead code and hidden risk. How to spot stale flags, remove them without breaking production, and stop them from piling up.
- Guides4 min read
What is a feature flag? A practical guide
Feature flags let you ship code switched off and turn it on without a deploy. How they work, the four kinds of flags, and the mistakes to avoid.
- Guides3 min read
Feature flags vs. configuration vs. environment variables
Feature flags, app configuration and environment variables all change behavior without changing code. When to use each one, with a simple decision table.
- Use cases2 min read
Kill switches: the feature flag you hope you never use
A kill switch is a feature flag that turns off a risky part of your system in seconds. Where to put them, how to design them, and how to make sure they work.