Community
Contribute & Discuss
openCCR is built by divers and engineers. Join the community, report issues, propose improvements, and help make CCR technology safer and more open.
All hardware design contributions must include fail-safe analysis. Software changes affecting sensor reading, PO₂ control, or alarm logic require peer review by at least two contributors with CCR diving experience. Never merge changes that reduce safety margins without community consensus and documented rationale. Rebreathers are life-support equipment — contributors are expected to treat them as such.
GitHub
Repositories
All openCCR code and hardware designs live on GitHub under open licenses.
openccr/hardware
KiCad electronic designs for the full openCCR platform: controller board, sensor conditioning boards, solenoid driver, HUD, display, and alert boards. Includes complete schematics, annotated BOM with Digi-Key and Mouser part numbers, production-ready Gerber files, drill maps, and pick-and-place centroid data. Licensed under CERN-OHL-S.
openccr/firmware
Embedded C/C++ firmware built on Zephyr RTOS and the Nordic nRF SDK. Implements the PO₂ control loop, multi-cell voting with outlier rejection, closed-loop solenoid actuation, depth-based setpoint changeover, tiered alarm management, Bühlmann ZHL-16C decompression algorithm, dive log recording, BLE connectivity, and the full rebus inter-board communication stack. Licensed under GPLv3.
openccr/companion-app
Flutter-based companion application for iOS and Android. Connects wirelessly over Bluetooth Low Energy. Features include PO₂ setpoint configuration, alarm threshold customisation, guided cell calibration wizard, firmware OTA updates, and a graphical dive log viewer with PO₂ trace, depth profile, and alarm event timeline. Licensed under GPLv3.
openccr/mechanics
Mechanical design files for all physical components of the openCCR platform. Contains STEP files for CAD integration and machining, STL files for 3D printing, and DXF/PDF 2D drawings with GD&T annotations. Covers electronics pressure housings, sensor mounting pods, scrubber canister interfaces, and breathing loop connectors. Each assembly includes material specs and O-ring groove geometry. Licensed under CERN-OHL-S.
openccr/docs
Central documentation repository for the entire openCCR platform. Home of the rebus protocol specification — the community-driven CAN-bus standard for rebreather interoperability. Also contains the system architecture overview, hardware integration guide, firmware porting guide, companion app API reference, and FMEA safety analysis summaries. Licensed under CC BY 4.0.
License
Open Licenses
openCCR uses a dual-licensing model. Community use is fully open. Commercial licenses are issued by the openCCR non-profit to fund development and ISO standardization.
Hardware
Schematics, PCB designs, and mechanical files are licensed under CERN Open Hardware Licence v2 — Strongly Reciprocal (CERN-OHL-S-2.0). Derivatives must be released under the same terms.
Firmware & Software
All firmware, libraries, and software tools are licensed under the GNU General Public License v3 (GPLv3). Copyleft — run, study, share, and modify freely. Distribute modified versions under the same GPLv3 terms.
Documentation
All documentation and written content is licensed under Creative Commons Attribution 4.0 International (CC BY 4.0). Share and adapt with attribution.
Commercial Services
Commercial Partners
The following companies offer commercial consulting services to rebreather manufacturers and vendors who wish to build customized hardware or software based on the openCCR platform. Whether you need custom sensor board variants, proprietary firmware features, regulatory validation, or full turn-key CCR electronics integration, these partners can work with you under commercial terms — without the copyleft obligations of the open-source licenses.
Partner Listings
Commercial partner listings to be updated.
Contributing
How to Contribute
From bug reports to hardware schematics — all contributions welcome. Read the full CONTRIBUTING.md before opening a PR.
openCCR operates a dual-licensing model to fund ongoing development and ISO standardization. By submitting a Pull Request, issue, or any contribution to this project, you agree that:
- Your contribution is governed by the openCCR Contributor License Agreement v1.0.
- You authorize the openCCR non-profit organization (and its authorized commercial partners) to utilize, modify, and dual-license your contributions without restriction.
You will be prompted to sign automatically on your first Pull Request via the CLA bot. Unsigned PRs cannot be merged. Read the full CLA →
1. Fork
Fork the relevant repository on GitHub and create a branch for your change.
2. Sign the CLA
The CLA bot will prompt you automatically on your first Pull Request. No manual steps needed.
3. Add License Headers
Hardware files: CERN-OHL-S-2.0. Software files: GPL-3.0-or-later header. See CONTRIBUTING.md for exact format.
Legal
Contributor License Agreement v1.0
Accepted automatically via CLA bot on your first Pull Request. Download CLA.md
1. Definitions
"Contribution" means any source code, hardware schematics, CAD files, documentation, or other material submitted by You to the Project.
2. Grant of Copyright License
Subject to the terms and conditions of this Agreement, You hereby grant to the openCCR Non-Profit Organization and its designated commercial entities a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Your Contributions and such derivative works.
3. Explicit Right to Dual-License
You explicitly acknowledge and agree that the Project operating model relies on dual-licensing. You grant the Project the unrestricted right to distribute Your Contributions under any license terms chosen by the Project management, including but not limited to:
- Permissive open-source licenses (e.g., MIT, Apache 2.0).
- Reciprocal copyleft open-source licenses (e.g., CERN-OHL-S, GPLv3).
- Proprietary, closed-source commercial licenses granted to enterprise partners by the Project's commercial arm.
4. Entitlement to Contribute
You represent that You are legally entitled to grant these licenses. If your employer has rights to intellectual property you create, you represent that you have received permission to make this Contribution.
Contact
Get in Touch
Open an issue on GitHub or start a discussion in the community forum.
Discussion Forum
GitHub Discussions link and contact information coming soon.