Blocks for developer products
For tools, SDKs and open source projects: the commands to start, the packages, the people behind it and who pays for it.
5 layouts
From install to your first rollout
Three commands in your project folder, and the first flag is live for your team.
- 1
Connect the project
Signs you in and writes the project key to your local environment file.
npx flags init - 2
Create a flag
It starts off for everyone, in every environment, until you say otherwise.
npx flags create new-checkout - 3
Roll it out
Turn it on for a share of your users and watch the numbers before going further.
npx flags rollout new-checkout --percent 10
An SDK for every stack
Typed, tested and kept in step with the API. Each one answers from memory, so a flag check never waits on the network.
TypeScript
Node, Deno, Bun and the browser.
npm install flagsPython
Django, Flask and FastAPI.
pip install flagsRuby
Rails and Sinatra.
gem install flagsPHP
Laravel and Symfony.
composer require flags/flagsRust
Async and blocking clients.
cargo add flagsKotlin
Android and the JVM.
implementation("flags:android:2.4.0")
Built by 340 people in the open
Two maintainers work on it full time. Everyone else fixes a bug, adds a translation or writes a page of the docs when they can.
Read the contributing guide
- +328
Good first issues
Small, well described and waiting for someone. Pick one, say hello in the thread and we will help you land it.
See every open issueKept independent by our sponsors
Sponsorships pay for two maintainers to work on the project full time. Every logo here helps keep it free.
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