feature-flags — open-source software health

PyPI · npm

99Exceptionalhealth index

aws-powertools/powertools-lambda-python

A developer toolkit to implement Serverless best practices and increase developer velocity.

Python★ 3,287↓ 15.3M/moSep 18, 2026

MIT-0Sep 18, 2026 · metrics 2.10.0

npm

98Exceptionalhealth index

PostHog/posthog-js

Send usage data from your web app or site to PostHog, with autocapture.

TypeScript★ 604↓ 116M/moSep 10, 2026

Custom licenseSep 10, 2026 · metrics 2.10.0

npm · PyPI

97Exceptionalhealth index

growthbook/growthbook

Open Source Feature Flags, Experimentation, and Product Analytics

TypeScript★ 8,364↓ 5.3M/moSep 15, 2026

Custom licenseSep 15, 2026 · metrics 2.10.0

npm · PyPI

96Exceptionalhealth index

Flagsmith/flagsmith

Flagsmith is an open source feature flagging and remote config service. Self-host or use our hosted version at https://app.flagsmith.com.

Python · TypeScript★ 6,532Aug 28, 2026

BSD-3-ClauseAug 28, 2026 · metrics 2.10.0

npm

96Exceptionalhealth index

Unleash/unleash

Open-source feature management platform

TypeScript★ 13.9K↓ 72.4K/moOct 17, 2026

AGPL-3.0Oct 17, 2026 · metrics 2.10.0

PyPI

96Exceptionalhealth index

launchdarkly/python-server-sdk

LaunchDarkly Server-side SDK for Python

Python★ 44↓ 9.4M/moOct 20, 2026

Custom licenseOct 20, 2026 · metrics 2.10.0

RubyGems

96Exceptionalhealth index

launchdarkly/ruby-server-sdk

LaunchDarkly Server-side SDK for Ruby

Ruby★ 54Oct 19, 2026

Custom licenseOct 19, 2026 · metrics 2.10.0

Go · npm

96Exceptionalhealth index

thomaspoignant/go-feature-flag

GO Feature Flag is a simple, complete and lightweight self-hosted cloud native feature flag solution 100% Open Source — built on OpenFeature 🎛️

Go · JavaScript · Python★ 2,125Oct 22, 2026

MITOct 22, 2026 · metrics 2.10.0

crates.io · PyPI · Go +1

94Exceptionalhealth index

PostHog/posthog

:hedgehog: PostHog is the leading platform for building self-driving products. Our developer tools – AI observability, analytics, session replay, flags, experiments, error tracking, logs, and more – capture all the context agents need to diagnose problems, uncover opportunities, and ship fixes. Steer it all from Slack, web, desktop, or the MCP.

Python · TypeScript★ 39.8K↓ 39/moSep 16, 2026

Custom licenseSep 16, 2026 · metrics 2.10.0

94Exceptionalhealth index

bucketeer-io/bucketeer

Feature Flag Management and A/B Testing platform

Go · TypeScript★ 479Sep 15, 2026

Apache-2.0Sep 15, 2026 · metrics 2.10.0

94Exceptionalhealth index

launchdarkly/ld-relay

LaunchDarkly Relay Proxy

Go★ 133Sep 9, 2026

Custom licenseSep 9, 2026 · metrics 2.10.0

PyPI

94Exceptionalhealth index

open-feature/python-sdk-contrib

Community contributions for hooks and reference providers in python

Python★ 27↓ 1.3M/moOct 15, 2026

No licenseOct 15, 2026 · metrics 2.10.0

npm

94Exceptionalhealth index

vercel/flags

Flags SDK by Vercel

TypeScript · MDX★ 617↓ 6.6M/moAug 27, 2026

MITAug 27, 2026 · metrics 2.10.0

Go · npm

93Exceptionalhealth index

PostHog/posthog-go

Official PostHog Go library

Go★ 55Sep 10, 2026

MITSep 10, 2026 · metrics 2.10.0

crates.io · Go · npm +1

92Excellenthealth index

juspay/superposition

Superposition is a context-based configuration management system designed to facilitate safe and flexible rollout of config changes

Rust · Java · Haskell★ 438↓ 105K/moOct 20, 2026

Apache-2.0Oct 20, 2026 · metrics 2.10.0

92Excellenthealth index

launchdarkly/go-server-sdk

LaunchDarkly Server-side SDK for Go

Go★ 49Sep 19, 2026

Custom licenseSep 19, 2026 · metrics 2.10.0

npm

92Excellenthealth index

launchdarkly/js-core

LaunchDarkly monorepo for JavaScript SDKs

TypeScript★ 28Sep 14, 2026

Custom licenseSep 14, 2026 · metrics 2.10.0

npm · crates.io · Go +3

91Excellenthealth index

flipt-io/flipt-client-sdks

Flipt Client-Side Evaluation SDKs

Rust · Go · TypeScript★ 31↓ 349.9K/moOct 20, 2026

MITOct 20, 2026 · metrics 2.10.0

Packagist

91Excellenthealth index

launchdarkly/php-server-sdk

LaunchDarkly Server-side SDK for PHP

PHP★ 39↓ 442.2K/moSep 12, 2026

Custom licenseSep 12, 2026 · metrics 2.10.0

npm

91Excellenthealth index

launchdarkly/react-client-sdk

LaunchDarkly Client-side SDK for React.js

TypeScript★ 90↓ 6.6M/moAug 27, 2026

Custom licenseAug 27, 2026 · metrics 2.10.0

npm

91Excellenthealth index

open-feature/spec

OpenFeature specification

Python · Gherkin★ 1,258Sep 19, 2026

Apache-2.0Sep 19, 2026 · metrics 2.10.0

npm · crates.io

90Excellenthealth index

GoPlasmatic/datalogic-rs

A fast JSONLogic rules engine: one Rust core with official bindings for Node.js, Python, Go, Java, .NET, PHP, and the browser (WASM), plus a React visual debugger.

Rust · TypeScript★ 93↓ 8,739/moOct 21, 2026

Apache-2.0Oct 21, 2026 · metrics 2.10.0

NuGet · npm

90Excellenthealth index

PostHog/posthog-dotnet

A dotnet client sdk to the PostHog API

C#★ 46Aug 25, 2026

MITAug 25, 2026 · metrics 2.10.0

NuGet

90Excellenthealth index

Unleash/unleash-dotnet-sdk

Unleash client SDK for .NET

C#★ 88Sep 17, 2026

Apache-2.0Sep 17, 2026 · metrics 2.10.0

npm

90Excellenthealth index

Unleash/unleash-node-sdk

Unleash client SDK for Node.js

TypeScript★ 226↓ 3.1M/moAug 27, 2026

Apache-2.0Aug 27, 2026 · metrics 2.10.0

npm · Go · crates.io +3

90Excellenthealth index

ops-ai/Toggly.FeatureManagement

Enables teams to release software faster and safer, and with better results.

TypeScript · C#★ 5↓ 58.8K/moOct 21, 2026

MITOct 21, 2026 · metrics 2.10.0

Maven

89Excellenthealth index

featurehub-io/featurehub

FeatureHub - cloud native feature flags, A/B testing and remote configuration service. Real-time streaming feature updates. Provided with Java, JavaScript, React, Python, Go, .Net, Ruby, Android, Swift and Flutter SDKs.

Dart · Kotlin · Groovy★ 361Sep 14, 2026

Custom licenseSep 14, 2026 · metrics 2.10.0

crates.io · Go

89Excellenthealth index