Open Sourcing Metalama
The biggest news this month: we’ve released Metalama 2025.1, our first open-source version!
This is big news for us and for the entire .NET ecosystem. While many open-source projects have announced their commercial transition this year, we’re going against the tide and have released 85% of Metalama’s codebase under the MIT license. We believe that vendor-led open-source projects are the most viable option for development tools, components, and libraries (except for IDEs and UI components, which have an established commercial market). As a result, the entire code generation and aspect-oriented programming feature is now open source, while IDE tooling, architecture verification, and some other extensions remain proprietary.
Curious about why we made this decision, what it means for you, and what’s next? Read the full story in my blog post, Metalama Is Now Open Source, along with my thoughts about the delicate balance between community-driven development and commercial sustainability.
If you haven’t already, please give us a star on GitHub to show your support!
Metalama 2025.1: Post-Release Updates
Since the general availability (GA) release of Metalama 2025.1, we’ve been busy listening to your feedback and rolling out fixes and improvements. Thank you to everyone who reported issues and shared suggestions!
Here’s a quick look at recent releases:
- 2025.1.6: Bug fixes and minor telemetry improvements.
- 2025.1.7: Major update: merged with Roslyn 4.14 for improved compatibility.
- 2025.1.8: Critical licensing bug fix, made
[Observable]applicable to interfaces, and further telemetry improvements. - 2025.1.9: Critical Visual Studio Extension (VSX) bug fix.
For the full changelog and all release notes, check out the GitHub Releases page. The Roslyn merge in 2025.1.7 is especially important: it keeps Metalama aligned with the latest C# language features and tooling.
Open Source Security Foundation Best Practices
As part of many critical supply chains, we’re taking security and best practices seriously. Our pipelines are now compliant with OpenSSF best practices.
Open Source Founder Summit in Paris
This month, I had the pleasure of attending the Open Source Founder Summit in Paris. It was inspiring to connect with fellow open-source leaders and dive deep into the realities of open-source business models, governance, and sustainability. I’ve captured my reflections and key takeaways in a dedicated LinkedIn article: Attending the Open Source Founder Summit in Paris. I share candid thoughts on open-source foundations, why I believe the .NET open-source community lags behind others, and why I don’t think this will change anytime soon. If you’re curious about my perspective, I invite you to give it a read!
Closing the Metalama Community Slack Workspace
As part of our transition to open source, we’ve closed the Metalama community Slack workspace, which previously served as a channel for brief news and technical support.
Going forward, real-time conversations with our core team on Slack or Teams will be reserved for enterprise customers. For the wider community, we encourage you to use GitHub Discussions for questions, ideas, and general conversation, or GitHub Issues for bug reports and feature requests. While we do monitor these channels, please note that our response times may be slower than before.
Metalama Briefs: Stay Tuned
To stay informed about the latest news, releases, and quick updates, visit our briefs page or subscribe to the RSS feed. This is the most reliable way to receive announcements about new builds and community updates, without worrying about social media algorithms filtering them out of your timeline.
Roadmap
After a busy and successful spring, we’re looking forward to slowing down during the summer, focusing on filling some remaining gaps between Metalama and PostSharp. In autumn, we plan to work on .NET 10 and C# 14 compatibility.
We’ve updated the roadmap to provide more clarity on upcoming features and releases:
June 2025
- Stabilize 2025.1.
- Migrate the issue database and project management to GitHub.
- Release PostSharp’s source code under our proprietary source-available license.
Summer 2025
- Metalama 2025.2: Filling gaps with PostSharp:
- Support for overriding event invocation.
- If time permits: interception of
awaitfor enhanced asynchronous programming capabilities.
Autumn 2025
- Metalama 2026.0: Compatibility with .NET 10 and C# 14:
- Ensuring full support for the latest language features and runtime improvements.
- Additional enhancements to streamline meta-programming workflows.
Conclusion
Metalama is now open source, and honestly, there’s no excuse left for writing repetitive code in .NET. Open source is about embracing transparency, security, and evolving how we do business. It means far more than throwing code over the wall. We’re still ironing out some details, but we’re committed to building a project that’s strong, reliable, and here to stay.
Thanks for being part of this. Now go write some aspects.
Happy meta-programming!