Caution
I'm repeating it again: Holy smokes, what a ride. Fluxer is taking off much earlier than I'd expected.
I know it's hard to resist, but please wait a little longer before you dive deep into the current codebase or try to set up self-hosting. I'm aware the current stack isn't very lightweight. I'm working on making self-hosting as straightforward as possible and the development environment likewise.
Self-hosted deployments won't include any traces of Plutonium, and nothing is paywalled. You can still configure your own tiers and limits in the admin panel.
Thanks for bearing with me. Development on Fluxer is about to get much easier, and the project will be made sustainable through community contributions and bounties for development work. Stay tuned – there's not much left now.
I thought I could take it a bit easier while shipping this stabilising update, but Discord's announcement in Februrary has changed things.
There's just been a lot of work involved in keeping the production deployment up and running, handling trust & safety concerns, answering support emails, handling billing issues, and working on the refactor at the same time. I'm really excited to open up development and make it easier for others to contribute, and I can't wait to see what the community builds on Fluxer!
As soon as the refactor is ready (not much longer now!), I'll enable PRs and interact more actively and push updates to this repository more frequently. The remaining parts of the refactor are currently being worked on and being tested live in production that has over 125,000 users (and we're only two full-time employees for now). After that, all work will happen openly in public.
The team is also growing, though we remain small and can't offer very competitive salaries just yet – but if you want to work part-time or contract on projects, or you think you're a great fit for the roles we're hiring for (though not as actively across all roles at this time, but we'll keep you on file for when we are), check out the careers page :D
❤️
Note
Learn about the developer behind Fluxer, the goals of the project, the tech stack, and what's coming next.
Fluxer is a free and open source instant messaging and VoIP platform for friends, groups, and communities. Self-host it and every feature is unlocked.
Real-time messaging – typing indicators, reactions, and threaded replies.
Voice & video – calls in communities and DMs with screen sharing, powered by LiveKit.
Rich media – link previews, image and video attachments, and GIF search via KLIPY.
Communities and channels – text and voice channels organised into categories with granular permissions.
Custom expressions – upload custom emojis and stickers for your community.
Self-hostable – run your own instance with full control of your data and no vendor lock-in.
Note
Native mobile apps and federation are top priorities. If you'd like to support this work, donations are greatly appreciated. You can also share feedback by emailing developers@fluxer.app.
Note
New to Fluxer? Follow the self-hosting guide for step-by-step setup instructions.
TBD
livekitctl– bootstrap a LiveKit SFU for voice and video
- TypeScript and Node.js for backend services
- Hono as the web framework for all HTTP services
- Erlang/OTP for the real-time WebSocket gateway (message routing and presence)
- React and Electron for the desktop and web client
- Rust compiled to WebAssembly for performance-critical client code
- SQLite for storage by default, with optional Cassandra for distributed deployments
- Meilisearch for full-text search and indexing
- Valkey (Redis-compatible) for caching, rate limiting, and ephemeral coordination
- LiveKit for voice and video infrastructure
Fluxer supports development through devenv only. It provides a reproducible Nix environment and a single, declarative process manager for the dev stack.
- Install Nix and devenv using the devenv getting started guide.
- Enter the environment:
devenv shellIf you use direnv, the repo includes a .envrc that loads devenv automatically – run direnv allow once.
Start all services and the development server with:
devenv upOpen the instance in a browser at your dev server URL (e.g. http://localhost:48763/).
Emails sent during development (verification codes, notifications, etc.) are captured by a local Mailpit instance. Access the inbox at your dev server URL + /mailpit/ (e.g. http://localhost:48763/mailpit/).
If you develop on a remote VM behind Cloudflare Tunnels (or a similar HTTP-only tunnel), voice and video won't work out of the box. Cloudflare Tunnels only proxy HTTP/WebSocket traffic, so WebRTC media transport needs a direct path to the server. Open these ports on the VM's firewall:
| Port | Protocol | Purpose |
|---|---|---|
| 3478 | UDP | TURN/STUN |
| 7881 | TCP | ICE-TCP fallback |
| 50000-50100 | UDP | RTP/RTCP media |
The bootstrap script configures LiveKit automatically based on domain.base_domain in your config.json. When set to a non-localhost domain, it enables external IP discovery so clients can connect directly for media while signaling continues through the tunnel.
There is experimental support for developing in a VS Code Dev Container / GitHub Codespace without Nix. The .devcontainer/ directory provides a Docker Compose setup with all required tooling and backing services.
# Inside the dev container, start all processes:
process-compose -f .devcontainer/process-compose.yml upOpen the app at http://localhost:48763 and the dev email inbox at http://localhost:48763/mailpit/. Predefined VS Code debugging targets are available in .vscode/launch.json.
Warning
Bluesky OAuth is disabled in the devcontainer because it requires HTTPS. All other features work normally.
To develop the documentation site with live preview:
pnpm dev:docsFluxer is free and open source software licensed under AGPLv3. Contributions are welcome.
See CONTRIBUTING.md for development processes and how to propose changes, and CODE_OF_CONDUCT.md for community guidelines.
Report vulnerabilities at fluxer.app/security. Do not use public issues for security reports.
License
Copyright (c) 2026 Fluxer Contributors
Licensed under the GNU Affero General Public License v3:
Copyright (c) 2026 Fluxer Contributors
This program is free software: you can redistribute it and/or modify it under
the terms of the GNU Affero General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option) any
later version.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
details.
You should have received a copy of the GNU Affero General Public License along
with this program. If not, see https://www.gnu.org/licenses/
See LICENSING.md for details on commercial licensing and the CLA.
