Open Source Application Security Tools
A curated collection of the best open source tools for securing software applications during development and runtime.
Secure secret management for modern development teams
Stars
28,801Last commit
21 hours agoLicense
MIT
End-to-end encrypted secret management platform for seamless integration and enhanced security in development workflows.
Open Source Alternative to:
Feature flags for rapid, risk-free software deployment
Stars
13,742Last commit
11 hours agoLicense
AGPL-3.0
A powerful feature management platform enabling gradual rollouts, A/B testing, and seamless integration for continuous delivery.
Open Source Alternative to:
Privacy-first CAPTCHA alternative with proof-of-work
Stars
7,517Last commit
3 days agoLicense
Apache-2.0
Lightweight open-source CAPTCHA solution using SHA-256 proof-of-work. 250x smaller than hCaptcha, fully customizable, and privacy-focused with zero telemetry.
Open Source Alternative to:
Open-source A/B testing and feature flagging platform
Stars
8,134Last commit
9 hours agoLicense
MIT
Powerful, developer-friendly experimentation tool for data-driven product decisions. Seamless integration, real-time insights, and flexible deployment.
Open Source Alternative to:
Feature flags and remote config for rapid deployment
Stars
6,517Last commit
9 hours agoLicense
BSD-3-Clause
Powerful feature management platform for seamless software releases, A/B testing, and personalized user experiences.
Open Source Alternative to:
Secure, policy-based access control for modern applications
Stars
4,541Last commit
23 hours agoLicense
Apache-2.0
A scalable authorization layer that provides fine-grained access control through externalized policies, enabling secure and flexible permissions management.
Open Source Alternative to:
Git-native feature management for developers
Stars
4,870Last commit
2 days agoLicense
GPL-3.0
A feature flag platform that integrates with Git workflows, enabling developers to manage features directly in their codebase.
Open Source Alternative to:
Open-source code security engine for developers
Stars
2,958Last commit
3 days agoLicense
LGPL-2.1
Opengrep is a community-driven fork of SemgrepCE, providing accessible static code analysis and security scanning for developers.
Next-Gen CAPTCHA and Spam Protection, GDPR compliant
Stars
2,672Last commit
3 days agoLicense
MIT
ALTCHA offers cutting-edge spam and abuse protection for websites and apps, with privacy-friendly CAPTCHA alternatives designed for GDPR compliance.
Open Source Alternative to:
Open-source feature flag management for seamless deployments
Stars
1,901Last commit
22 hours agoLicense
MIT
FeatBit is a fast, scalable feature flag service that enables risk mitigation and fosters business growth through controlled feature releases.
Open Source Alternative to:
Privacy-first proof-of-work CAPTCHA without user friction
Stars
2,481Last commit
10 months agoLicense
AGPL-3.0
Privacy-focused proof-of-work CAPTCHA system that silently protects websites without tracking users or requiring image solving. Drop-in replacement for reCAPTCHA.
Open Source Alternative to:
Feature management with GitOps for developers
Stars
805Last commit
7 days agoLicense
MIT
Featurevisor is an open-source tool for managing feature flags, experiments, and remote configuration directly from your Git repository.
Open Source Alternative to:
Decentralized CAPTCHA for enhanced web security
Stars
297Last commit
13 hours agoLicense
Apache-2.0
A blockchain-based CAPTCHA solution offering improved security, user experience, and resistance to bot attacks for web applications.
Open Source Alternative to:
GDPR-compliant bot protection without user friction
Stars
185Last commit
1 day agoLicense
Unknown
Privacy-first CAPTCHA service that blocks bots while keeping forms accessible. No puzzles, no tracking, no cookies - just invisible cryptographic protection.
Open Source Alternative to:
Type-safe feature flags and remote config for developers
Stars
167Last commit
1 year agoLicense
AGPL-3.0
Abby offers open-source, fully typed feature flagging and remote configuration for React and Next.js, with multi-environment testing and debugging tools.
Open Source Alternative to:
Invisible bot protection that respects user privacy
Stars
32Last commit
4 days agoLicense
MPL-2.0
Privacy-compliant CAPTCHA alternative using proof-of-work technology. Protects websites from bots and spam without user interaction or data tracking.
Open Source Alternative to:
Stellar Hosted – Managed Open Source software hosting in the EU: secure, compliant, fast.
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