head to head · open source
Lemmy vs pump.io
Lemmy has 14,599 GitHub stars, 966 forks, 129 open issues and last shipped 2 days ago. pump.io has 2,238 stars, 328 forks, 679 open issues and last shipped 7 months ago. Lemmy leads on adoption by 552% (14,599 vs 2,238 stars). Lemmy is written in Rust under AGPL-3.0; pump.io is written in JavaScript under Apache-2.0. Lemmy has attracted 7% as many forks as stars, pump.io 15%. Lemmy was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Lemmy | pump.io | |
|---|---|---|
| GitHub stars | ★ 15K | ★ 2.2K |
| License | AGPL-3.0 | Apache-2.0 |
| Written in | Rust | JavaScript |
| Last push | 2026-09-16 | 2026-02-12 |
| Forks | ⑂ 966 | ⑂ 328 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Lemmy if
- You weight community size — 15K stars and counting
- You want the AGPL-3.0 license terms
- Your stack matches Rust
- You value the larger contributor base for long-term maintenance
pick pump.io if
- You want the pump.io feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches JavaScript
- You evaluated both and pump.io fits your workflow better
About Lemmy
Lemmy is a link aggregator and forum platform for the Fediverse, written in Rust and released under the AGPL 3.0 license. It supports communities where users subscribe to forums, post links and discussions, vote, and comment. Each server can operate independently while remaining federated through ActivityPub, so users on one server can interact with users and communities on other servers.
read the full Lemmy overview →
About pump.io
pump.io is a social server and stream server written in JavaScript for Node.js, and it lives in the open source ActivityStreams and social networking ecosystem. The project provides an ActivityStreams API, uses activitystrea.ms JSON as the main data and command format, and includes a web interface. Its documented purpose is to let a person post something and have followers see it, while also exposing social data in a machine readable form.
read the full pump.io overview →
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Frequently asked questions
Is Lemmy or pump.io more popular?
Lemmy has 14,599 GitHub stars and pump.io has 2,238. Lemmy has the larger community by that measure.
Are Lemmy and pump.io free?
Both are open source. Lemmy is licensed under AGPL-3.0 and pump.io under Apache-2.0. Neither carries a licence fee.
What is the difference between Lemmy and pump.io?
Lemmy is written in Rust and pump.io in JavaScript. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Lemmy or pump.io?
Choose Lemmy if you want the larger community (14,599 stars) or its AGPL-3.0 licence terms. Choose pump.io if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.