Important Announcement: OCCT 8.0 Release and Patch Migration Process

[dpasukhi]

Dear OCCT Community,

We're pleased to announce that OCCT 8.0 will be released at the start of 2026. In preparation for this major release, we want to share some important information:

Version Changes and Repository Restructuring

• API Stability Commitment: We're committed to maintaining API stability to the greatest extent possible. Our primary goal is to modernize the repository structure while minimizing API changes.
• Release 7.9 includes changes that impact custom external patches built on previous versions
• The 7.9 changes and ongoing changes for 8.0 have minimal impact on the API, but significantly improve code consistency and repository structure
• OCCT 8.0 will introduce a complete repository restructuring to address the high complexity of the current structure
• The restructuring aims to make the codebase more maintainable and easier to use for all stakeholders
• We'll be integrating GTest for each toolkit, which will be better implemented within the new, simplified structure

Patch Migration Program

We're announcing a program to help migrate existing patches to the latest version. The OCCT team will perform the migration work, but we need patch authors' help to validate the migrated patches.

Branches Open for Integration:

• IR
• OCCT-7.6
• OCCT-7.7
• OCCT-7.8
• OCCT-7.9

Important Note About IR- Branches*: These branches will be maintained without modifications and will serve exclusively as targets for migrating old patches. The IR branch is similar to the develop branch and is updated frequently to represent the latest version. These branches are specifically preserved to maintain compatibility with older patches during the migration process.

Integration Process:

1. Fork the OCCT repository: https://github.com/Open-Cascade-SAS/OCCT
2. Create a branch in your fork for the patch to be integrated
3. Add a DRAW test or provide equivalent C++ code in the PR description
4. Sign the Contributor License Agreement (CLA) if you haven't already: https://dev.opencascade.org/get_involved
5. Create a pull request from your branch to the corresponding OCCT repository branch
   • No need to create separate issues, but please include all necessary information in the PR description
   • Indicate your availability to collaborate on the review process
6. The OCCT team will review your PR and request changes if needed
7. We will migrate your patch from the old version to the new one (e.g., from 7.7 to 8.0.0dev)
8. We will run DRAW tests and may ask you to run tests on your side
9. Once validated, we will merge the pull request

Testing Process

Pull requests to the IR branches will undergo comprehensive testing, including:

• Full build verification
• Complete DRAW test suite
• Code formatting validation

All test results, including build outputs and DRAW test results, are stored as GitHub Action artifacts for transparency and reference. This ensures that all contributions maintain the quality standards expected for OCCT.

While we cannot guarantee all patches will be integrated, we will make our best effort to include as many as possible. The only requirements are a signed CLA and your cooperation during the process.

Commercial Services

Our team also offers the following commercial services:

• Migration of new patches to previous OCCT versions or custom branches
• Migration of client software to newer OCCT versions or custom branches
• Consulting on OCCT integration and customization
• Development of new features and priority bug fixes
• Training for your team on working with OCCT
• E-learning courses related to OCCT

For more information about our commercial services, please contact us directly or check OCCT3D

Best regards,
OCCT3D Team