Free universal database tool and SQL client

Learn System Design concepts and prepare for interviews using free resources.

Open Source Identity and Access Management For Modern Applications and Services

Apache Kafka - A distributed event streaming platform

Conductor is an event driven agentic orchestration platform providing durable and highly resilient execution engine for applications and AI Agents

Browse media content with your own rules on Android TV

Apache Pulsar - distributed pub-sub messaging system

Open source alternative to Auth0 / Firebase Auth / AWS Cognito

Access your entire server infrastructure from your local desktop

🔎 Open source distributed and RESTful search engine.

A free, secure and open source app for Android to manage your 2-step verification tokens.

Apereo CAS - Identity & Single Sign On for all earthlings and beyond.

Server supporting the Signal Private Messenger applications on Android, Desktop, and iOS

Traccar GPS Tracking System

Open-Source Subscription Billing & Payments Platform

Jitsi is an audio/video and chat communicator that supports protocols such as SIP, XMPP/Jabber, IRC and many other useful features.

Fully featured, open source, privacy friendly email app for Android

Distributed Peer-to-Peer Web Search Engine and Intranet Search Appliance

[Unmaintained] Open source two-factor authentication for Android

Database Subsetting and Relational Data Browsing Tool.

Download apks from Google Play Store

Android open source calendar

The most beautiful SMS messenger for Android - Revived

Proactive, Open source API security → API discovery, API Security Posture, Testing in CI/CD, Test Library with 1000+ Tests, Add custom tests, Sensitive data exposure

CATS is a REST API Fuzzer and negative testing tool for OpenAPI endpoints. CATS automatically generates, runs and reports tests with minimum configuration and no coding effort. Tests are self-heali…

Digital Signature Service : creation, extension and validation of advanced electronic signatures

See http://www.zenz-solutions.de/personaldnsfilter for details

OAuth 2.0 server and client; OpenID Connect Provider (OP) & UMA Authorization Server (AS)

SignServer – Open source, PKI-based signing software to sign code, documents, timestamps and more.