A Curated List of Influential Open‑Source Projects That Support Thousands of Developers

Based on a discussion from Zhihu about "Which niche open‑source projects have sustained a large number of people?", the author compiles a list of influential projects that have become essential tools for developers across various domains.

1. Skynet – A lightweight distributed game server framework written in C, only a few thousand lines of code, supporting high concurrency, RPC communication, and message queues. Widely used in many Chinese game back‑ends. GitHub

2. flv.js – A JavaScript library from the Bilibili team for playing FLV video in HTML5 via Media Source Extensions. Maintenance is decreasing; for live streams consider mpegts.js. GitHub

3. Tinyhttpd – An ultra‑lightweight HTTP server with fewer than 500 lines of code, mainly for educational purposes to help developers understand HTTP fundamentals. GitHub

4. Memcached & Redis – Memcached is a simple high‑performance cache system; Redis is a feature‑rich key‑value store supporting many data structures, persistence, and use cases such as queues and leaderboards. Memcached GitHub | Redis GitHub

5. cJSON – A lightweight JSON parsing library written in about 500 lines of C, ideal for embedded and low‑resource environments. Used widely in IoT and industrial control. GitHub

6. LevelDB – A high‑performance key‑value store open‑sourced by Google, suitable for large‑scale data scenarios and used in projects like Bitcoin and TiDB. GitHub

7. Libevent – A high‑performance event notification library in C, providing a generic asynchronous event handling mechanism. Powers Nginx, Memcached and many other projects. GitHub

8. SQLite – An embedded relational database stored in a single file, supporting standard SQL. Deployed in mobile apps, desktop software, and many web services. GitHub

9. OpenResty – A web platform based on Nginx that extends functionality with Lua scripts, widely used for API gateways and micro‑service gateways in cloud environments. GitHub

10. MeiliSearch – An open‑source, high‑performance full‑text search engine written in Rust, designed for modern web applications. GitHub

11. FreeSwitch – An open‑source telephony platform used by a majority of Chinese call centers. GitHub

12. ffmpeg – A powerful multimedia framework supporting a vast array of audio and video formats, essential for media processing pipelines. GitHub

13. ImageMagick – A versatile image manipulation suite supporting numerous formats, widely adopted for server‑side image processing. GitHub

14. CEF – The Chromium Embedded Framework provides a C++ wrapper around the Chrome engine, used in desktop applications such as NetEase Cloud Music, QQ, WeChat, and Photoshop. GitHub

15. OBS Studio – A free, open‑source tool for video recording and live streaming, powering many Chinese streaming platforms. GitHub

16. VirtualApp – An Android sandbox product that creates lightweight virtual machines, enabling app multi‑instance, plugin development, and isolation. GitHub

17. VideoCrafter – An open‑source video generation and editing toolbox from Tencent AI Lab and HKUST, offering Text‑to‑Video and Image‑to‑Video capabilities. GitHub

18. OpenCV – The Open Source Computer Vision Library, a cornerstone for image processing, video analysis, object detection, and robotics. GitHub

19. draw.io – A web‑based diagramming tool that runs entirely in the browser, supporting flowcharts, UML, network diagrams, and more. GitHub

20. OpenSSL – An open‑source cryptographic toolkit implementing SSL/TLS and a wide range of encryption algorithms, fundamental to secure Internet communications. GitHub

The author concludes that open‑source projects act as accelerators for technological progress, breaking barriers and enabling global collaboration.