Strong copyleft open-source software in 2026
If you distribute the program or anything built on it, you must release the whole source under the same license. 304 projects here use GPL-2.0 (44), GPL-3.0 (254), OSL-3.0 (4) and EUPL-1.2 (2).
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1
Netdata netdata
The fastest path to AI-powered full stack observability, even for lean teams.
Complete system Production-ready You want detailed server and container monitoring running within minutes without building Prometheus and Grafana yourself.
★ 81k GPL-3.0 Go Active, pushed today -
2
OBS Studio obsproject
OBS Studio - Free and open source software for live streaming and screen recording
Complete system Production-ready You record tutorials or stream to Twitch, YouTube and similar platforms.
★ 79k GPL-2.0 C Active, pushed today -
3
Jellyfin jellyfin
The Free Software Media System - Server Backend & API
Complete system Production-ready You want Plex or Emby features without accounts, subscriptions or a vendor cloud.
★ 59k GPL-2.0 C# Active, pushed 2 days ago -
4
Paperless-ngx paperless-ngx
A community-supported supercharged document management system: scan, index and archive all your documents
Complete system Production-ready A household or small office wants to go paperless and can run Docker.
★ 47k GPL-3.0 Python Active, pushed 4 days ago -
5
LosslessCut mifi
The swiss army knife of lossless video/audio editing
Complete system Production-ready You need to cut large recordings quickly without losing quality.
★ 46k GPL-2.0 TypeScript Active, pushed today -
6
ERPNext frappe
Free and Open Source Enterprise Resource Planning (ERP)
Complete system Production-ready A small or mid-size business wants a complete ERP with no paid edition, and can self-host or use Frappe Cloud.
★ 41k GPL-3.0 Python Active, pushed 6 days ago -
7
ShareX ShareX
ShareX is a free and open-source application that enables users to capture or record any area of their screen with a single keystroke. It also supports uploading images, text, and various file types to a wide range of destinations.
Complete system Production-ready You capture and share screenshots constantly on Windows and want automation after each capture.
★ 41k GPL-3.0 C# Active, pushed today -
8
Halo halo-dev
Halo 是一款强大易用的开源建站工具，从个人博客、知识库，到企业官网、在线商城，Halo 都能助您轻松实现，一站式满足您的多样化建站需求。
Complete system Production-ready You want a WordPress-style site builder with a strong Chinese community and plugin market.
★ 40k GPL-3.0 Java Active, pushed today -
9
AdGuardHome AdguardTeam
Network-wide ads & trackers blocking DNS server
Complete system Production-ready You want Pi-hole-style blocking with built-in DoH, DoT and DoQ in a single binary.
★ 38k GPL-3.0 TypeScript Active, pushed today -
10
Cloudreve cloudreve
🌩 Self-hosted file management and sharing system, supports multiple storage providers
Complete system Production-ready You want a personal or small-team cloud drive over existing storage with sharing links.
★ 29k GPL-3.0 Go Active, pushed 13 days ago -
11
Typesense typesense
Open Source alternative to Algolia + Pinecone and an Easier-to-Use alternative to ElasticSearch ⚡ 🔍 ✨ Fast, typo tolerant, in-memory fuzzy Search Engine for building delightful search experiences
Building block Production-ready You want Algolia-style instant search for a site or app that you can self-host cheaply.
★ 27k GPL-3.0 C++ Active, pushed 3 days ago -
12
Solidity argotorg
Solidity, the Smart Contract Programming Language
Developer tool Production-ready You are writing smart contracts for Ethereum or an EVM-compatible chain.
★ 26k GPL-3.0 C++ Active, pushed today -
13
Tasmota arendst
Alternative firmware for ESP8266 and ESP32 based devices with easy configuration using webUI, OTA updates, automation using timers or rules, expandability and entirely local control over MQTT, HTTP, Serial or KNX. Full documentation at
Complete system Production-ready You want cloud-free control of cheap Wi-Fi smart devices and can flash firmware.
★ 25k GPL-3.0 C Active, pushed today -
14
Navidrome navidrome
🎧 Your Personal Streaming Service
Complete system Production-ready You own a music library and want Spotify-style access to it from any device.
★ 24k GPL-3.0 Go Active, pushed today -
15
Cloc AlDanial
cloc counts blank lines, comment lines, and physical lines of source code in many programming languages.
Developer tool Production-ready You need a quick breakdown of a codebase's size by language.
★ 24k GPL-2.0 Perl Active, pushed 8 days ago -
16
JDK openjdk
JDK main-line development https://openjdk.org/projects/jdk
Developer tool Production-ready You work on the JDK itself; most teams should install a built distribution such as Temurin.
★ 23k GPL-2.0 Java Active, pushed today -
17
Matomo matomo-org
Empowering People Ethically 🚀 — Matomo is hiring! Join us → https://matomo.org/jobs Matomo is the leading open-source alternative to Google Analytics, giving you complete control and built-in privacy. Easily collect, visualise, and analyse data from websites & apps. Star us on GitHub ⭐️ – Pull Requests welcome!
Complete system Production-ready An organisation needs detailed analytics under its own control, for example for privacy rules in the public sector or EU.
★ 22k GPL-3.0 PHP Active, pushed today -
18
Community-skeleton uvdesk
UVdesk Open Source Community Helpdesk is a comprehensive ticketing support system designed for everyone, offering robust features to streamline customer support and collaboration.
Complete system Usable You want a free PHP helpdesk and can live with a slower release pace.
★ 20k OSL-3.0 CSS Active, pushed 26 days ago -
19
Screenity alyssaxuu
The free and privacy-friendly screen recorder with no limits 🎥
Complete system Production-ready You want Loom-style recordings without an account or watermark.
★ 19k GPL-3.0 JavaScript Active, pushed 8 days ago -
20
OpenRA OpenRA
Open Source real-time strategy game engine for early Westwood games such as Command & Conquer: Red Alert written in C# using SDL and OpenGL. Runs on Windows, Linux, *BSD and Mac OS X.
Complete system Production-ready You want to play or mod classic Command & Conquer games on modern systems.
★ 18k GPL-3.0 C# Active, pushed 5 days ago -
21
Zola getzola
A fast static site generator in a single binary with everything built-in. https://www.getzola.org
Developer tool Production-ready You want a Hugo-like single-binary generator with simpler templates for a blog or docs site.
★ 18k EUPL-1.2 Rust Active, pushed today -
22
Neo4j neo4j
Graphs for Everyone
Building block Production-ready Your queries are mostly about relationships several hops deep, which are awkward in SQL.
★ 17k GPL-3.0 Java Active, pushed 11 days ago -
23
OpenProject opf
OpenProject is the leading open source project management software for product, project and portfolio management. A powerful Jira alternative with agile planning, issue tracking, roadmaps, Gantt charts, time tracking, collaboration features, and more. Available on premises or in the cloud. ⭐ Star us on GitHub
Complete system Production-ready An organisation, especially in the public sector or EU, needs classic project management with data sovereignty.
★ 17k GPL-3.0 Ruby Active, pushed 5 days ago -
24
Quarkdown iamgio
🪐 Markdown with superpowers: from ideas to papers, presentations, websites, books, and knowledge bases.
Developer tool Usable You write papers, books or presentations and want Markdown with LaTeX-like layout control.
★ 16k GPL-3.0 Kotlin Active, pushed yesterday -
25
Zigbee2MQTT Koenkk
Zigbee 🐝 to MQTT bridge 🌉, get rid of your proprietary Zigbee bridges 🔨
Integration Production-ready You run Home Assistant or another MQTT-based system and want broad Zigbee device support without proprietary bridges.
★ 16k GPL-3.0 TypeScript Active, pushed 2 days ago -
26
Shotcut mltframework
cross-platform (Qt), open-source (GPLv3) video editor
Complete system Production-ready You need a capable free editor for YouTube, training or marketing videos on any OS.
★ 16k GPL-3.0 C++ Active, pushed today -
27
Easydict tisfeng
一个简洁优雅的词典翻译 macOS App。开箱即用，支持离线 OCR 识别，支持有道词典，🍎 苹果系统词典，🍎 苹果系统翻译，OpenAI，Gemini，DeepL，Google，Bing，腾讯，百度，阿里，小牛，彩云和火山翻译。A concise and elegant Dictionary and Translator macOS App for looking up words and translating text.
Complete system Production-ready You read or write in several languages on a Mac and want quick lookups.
★ 15k GPL-3.0 Swift Active, pushed 7 days ago -
28
Audiobookshelf advplyr
Self-hosted audiobook and podcast server
Complete system Production-ready You own audiobook files or follow podcasts and want them streamed to your phone with synced progress.
★ 15k GPL-3.0 JavaScript Active, pushed yesterday -
29
Notesnook streetwriters
A fully open source & end-to-end encrypted note taking alternative to Evernote.
Complete system Production-ready Privacy matters most and you want encrypted notes synced across devices.
★ 15k GPL-3.0 TypeScript Active, pushed today -
30
Palmier Pro palmier-io
macOS video editor built for AI
Complete system Usable You want an AI-centred Mac video editor and accept that current versions are proprietary.
★ 15k GPL-3.0 Swift Active, pushed today -
31
LunaTranslator HIllya51
视觉小说翻译器 / Visual Novel Translator
Complete system Production-ready You play Japanese visual novels and want live translation.
★ 14k GPL-3.0 C++ Active, pushed 15 days ago -
32
Mailcow-dockerized mailcow
mailcow: dockerized - 🐮 + 🐋 = 💕
Complete system Production-ready You want to host email for several domains yourself with a full admin interface.
★ 14k GPL-3.0 JavaScript Active, pushed yesterday -
33
Chat tinode
Instant messaging platform. Backend in Go. Clients: Swift iOS, Java Android, JS webapp, scriptable command line; chatbots
Complete system Usable You want to embed or run your own messaging service with ready clients.
★ 14k GPL-3.0 Go Active, pushed 8 days ago -
34
Darktable darktable-org
darktable is an open source photography workflow application and raw developer
Complete system Production-ready You shoot raw and want a free Lightroom alternative.
★ 13k GPL-3.0 C Active, pushed today -
35
NoteGen codexu
Capture first. Organize later. A local-first Markdown app that turns scattered records into clear notes with AI.
Complete system Usable You collect scattered snippets during the day and want AI to draft notes from them.
★ 13k GPL-3.0 TypeScript Active, pushed today -
36
Magento2 magento
Prior to making any Submission(s), you must sign an Adobe Contributor License Agreement, available here at: https://opensource.adobe.com/cla.html. All Submissions you make to Adobe Inc. and its affiliates, assigns and subsidiaries (collectively “Adobe”) are subject to the terms of the Adobe Contributor License Agreement.
Complete system Production-ready A mid-size or large merchant needs deep customisation and has access to experienced Magento developers and hosting.
★ 12k OSL-3.0 PHP Active, pushed 11 days ago -
37
Manticoresearch manticoresoftware
Open-source search database for full-text, vector, and hybrid search with real-time indexing and SQL.
Building block Production-ready You want a lighter Elasticsearch alternative and like querying search with SQL.
★ 12k GPL-3.0 C++ Active, pushed today -
38
Rnote flxzt
Sketch and take handwritten notes.
Complete system Usable You take handwritten notes on a Linux laptop or tablet.
★ 12k GPL-3.0 Rust Active, pushed yesterday -
39
GCC gcc-mirror
Developer tool Production-ready You need the GCC source; most users install GCC from their system's packages.
★ 11k GPL-2.0 C++ Active, pushed today -
40
X-AnyLabeling CVHub520
X-AnyLabeling: A lightweight, efficient, and unified cross-platform desktop application for annotating text, image, video, point cloud and multimodal data, combining versatile built-in tools with state-of-the-art AI models and flexible multi-format export.
Developer tool Production-ready You build computer-vision datasets and want AI-assisted labelling on your own machine.
★ 11k GPL-3.0 Python Active, pushed 2 days ago -
41
Krita KDE
Krita is a free and open source cross-platform application that offers an end-to-end solution for creating digital art files from scratch built on the KDE and Qt frameworks.
Complete system Production-ready You want a professional-grade painting app without a subscription.
★ 11k GPL-3.0 C++ Active, pushed today -
42
LMMS LMMS
Cross-platform music production software
Complete system Usable You want a free FL Studio-like DAW for composing electronic music.
★ 11k GPL-2.0 C++ Active, pushed today -
43
WooCommerce woocommerce
A customizable, open-source ecommerce platform built on WordPress. Build any commerce solution you can imagine.
Complete system Production-ready A small or mid-size business already on WordPress, or wanting content and shop in one, sells online.
★ 11k GPL-2.0 PHP Active, pushed 5 days ago -
44
Manga Image Translator zyddnys
Translate manga/image 一键翻译各类图片内文字 https://cotrans.touhou.ai/ (no longer working)
Complete system Usable You want machine-translated manga pages and can run a GPU model locally.
★ 11k GPL-3.0 Python Active, pushed 22 days ago -
45
EverShop evershopcommerce
🛍️ Typescript E-commerce Platform
Complete system Usable A JavaScript team wants a modern, self-hosted store it can extend in TypeScript.
★ 11k GPL-3.0 TypeScript Active, pushed 7 days ago -
46
DnsServer TechnitiumSoftware
Technitium DNS Server
Complete system Production-ready You want a full DNS server for your home or office, including authoritative zones, not just a blocker.
★ 10k GPL-3.0 C# Active, pushed 9 days ago -
47
HRMS frappe
Open Source HR and Payroll Software
Complete system Production-ready A small or mid-size business wants open-source HR and payroll, especially alongside ERPNext.
★ 9k GPL-3.0 Python Active, pushed today -
48
Wallos ellite
Wallos: Open-source, self-hostable personal subscription tracker. Visualize your recurring expenses, manage your budget, and save money.
Complete system Production-ready You want to see and control what all your subscriptions cost each month.
★ 8.8k GPL-3.0 PHP Active, pushed yesterday -
49
TubeArchivist tubearchivist
Your self hosted YouTube media server
Complete system Usable You want to keep a searchable offline copy of YouTube channels you follow.
★ 8.6k GPL-3.0 Python Active, pushed 9 days ago -
50
JimuReport jeecgboot
一款真正的 AI 报表诞生了！JimuChatBI —— 首款免费开源对话式智能数据分析产品（Chat2BI）。 一句话生成报表和数据大屏，支持对话式 AI 修改优化；类 Excel 在线报表设计，兼容国产信创数据源。 对着 AI 说句话，报表就出来了——表格、图表、分组汇总自动生成，复杂报表场景轻松应对。想做数据大屏？同样一句话搞定，让数据分析进入 AI 时代。
Complete system Production-ready A Chinese business wants a free FineReport-style tool for complex printed reports.
★ 8.6k GPL-3.0 Java Active, pushed yesterday -
51
MariaDB Server MariaDB
MariaDB server is a community developed fork of MySQL server. Started by core members of the original MySQL team, MariaDB actively works with outside developers to deliver the most featureful, stable, and sanely licensed open SQL server in the industry.
Building block Production-ready You need a MySQL-compatible database under the GPL, or run software that targets MySQL or MariaDB.
★ 8.5k GPL-2.0 C++ Active, pushed today -
52
Dolibarr Dolibarr
Dolibarr ERP CRM is a modern software package to manage your company or foundation's activity (contacts, suppliers, invoices, orders, stocks, agenda, accounting, ...). it's an open source Web application (written in PHP) designed for businesses of any sizes, foundations and freelancers.
Complete system Production-ready A small business, freelancer or association wants a mature, fully open ERP that runs on cheap PHP hosting.
★ 7.8k GPL-3.0 PHP Active, pushed today -
53
Backrest garethgeorge
Backrest is a web UI and orchestrator for restic backup.
Complete system Usable You like restic but want scheduling, notifications and browsing snapshots in a browser.
★ 7.8k GPL-3.0 TypeScript Active, pushed 42 days ago -
54
ReadYou ReadYouApp
An Android RSS reader presented in Material You style.
Complete system Usable You want a good-looking free feed reader on Android.
★ 7.6k GPL-3.0 Kotlin Active, pushed 3 months ago -
55
KeePassDX Kunzisoft
Lightweight vault and password manager for Android, KeePassDX allows editing encrypted data in a single file in KeePass format and fill in the forms in a secure way.
Complete system Production-ready You keep passwords in a KeePass file and need an Android app that reads and writes it.
★ 7.6k GPL-3.0 Kotlin Active, pushed yesterday -
56
Moodle moodle
Moodle - the world's open source learning platform
Complete system Production-ready A school, university or company needs a self-hosted LMS with a large ecosystem of plugins and hosting partners.
★ 7.6k GPL-3.0 PHP Active, pushed 4 days ago -
57
Android-DataBackup XayahSuSuSu
DataBackup for Android 7.0+
Complete system Usable Your Android phone is rooted and you want full app-plus-data backups when switching ROMs or devices.
★ 7.6k GPL-3.0 Kotlin Active, pushed 9 days ago -
58
Publii GetPublii
The most intuitive Static Site CMS designed for SEO-optimized and privacy-focused websites.
Complete system Production-ready A non-developer wants a fast static blog or small business site without running a server.
★ 7.4k GPL-3.0 HTML Active, pushed today -
59
eSearch xushengfeng
截屏 离线OCR 搜索翻译 以图搜图 贴图 录屏 万向滚动截屏 屏幕翻译 Screenshot Offline OCR Search Translate Search for picture Paste the picture on the screen Screen recorder Omnidirectional scrolling screenshot Screen translator 支持Windows Linux macOS
Complete system Production-ready You want one free tool for screenshots plus OCR and translation, especially on Linux.
★ 7.4k GPL-3.0 TypeScript Active, pushed today -
60
Jrnl jrnl-org
Collect your thoughts and notes without leaving the command line.
Developer tool Production-ready You want to keep a journal or work log from the terminal.
★ 7.4k GPL-3.0 Python Active, pushed today
Other license families
This is a plain summary, not legal advice. The license text in each repository is what binds.