Spectrum 2
Spectrum 2 is an open source instant messaging transport. It allows users to chat together even when they are using different IM networks.
- Team Chat
- C++
- GPL-3.0
- Actively maintained
GitHub stats
- GitHub stars
- 421
- Forks
- 92
- Open issues
- 19
- Commits, last 12 months
- 76
- Last commit
- Sep 24, 2026
- Latest release
- 2.2.1Jun 12, 2023
- Created
- Feb 10, 2011
Data from the GitHub API, refreshed daily.
About Spectrum 2
Spectrum 2 is an open source instant messaging transport. It allows users to chat together even when they are using different IM networks. Spectrum 2 is open source under the GPL-3.0 license and written mainly in C++, so you can read the code, run it on your own hardware and keep full control of your data.
The project has 421 stars and 92 forks on GitHub, with 76 commits over the last year. It installs natively rather than through an official Docker image, so plan for a short manual setup.
Repository preview
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What is Spectrum 2?
Spectrum 2 is a free, open-source app you can host on your own server, listed in our Team Chat category. Spectrum 2 is an open source instant messaging transport. It allows users to chat together even when they are using different IM networks. The source code lives at github.com/SpectrumIM/spectrum2, where it has 421 stars.
Is Spectrum 2 free and open source?
Yes. Spectrum 2 is open-source software released under the GPL-3.0 license, so you can self-host it at no cost. You only pay for the server it runs on, and some projects also offer an optional paid cloud plan.
Can I run Spectrum 2 with Docker?
Spectrum 2 does not list an official Docker image. It installs natively (C++), so follow the install steps in its README or look for a community-maintained container.
What are the best alternatives to Spectrum 2?
Popular open-source alternatives to Spectrum 2 include Rocket.Chat, Novu and Mattermost.
Is Spectrum 2 actively maintained?
The most recent commit to Spectrum 2 was on Sep 24, 2026 with 76 commits in the past twelve months. The latest release is 2.2.1, published Jun 12, 2023. Check the open issues on GitHub to gauge how quickly maintainers respond.