Working with the High Energy Physics Software Foundation (HSF) at CERN on the Phoenix project has been an incredible learning experience. Today, I'm excited to share a major technical milestone: my PR to migrate the entire project to Angular 20 has been merged!

Massive Angular 20 Upgrade

This was a complex architectural update. The Pull Request, titled "fix: add Angular 20 compatibility by upgrading dependencies and migrating to application builder (#806)", tackled several deep dependency issues.

The core challenge was that Angular 20 deprecated several internal APIs (like afterRender) and legacy builders. To fix this, I had to:

  • Upgrade @angular/core, @angular/cdk, and all related packages to v20.
  • Migrate angular.json from the legacy Webpack-based browser builder to the modern esbuild application builder.
  • Upgrade TypeScript to v5.8.2 and align zone.js requirements.

After thorough local testing to ensure the library and app builds passed with zero errors, it was reviewed by Copilot AI and approved and merged by the maintainers!

Screenshot of merged CERN Phoenix Pull Request

This was a fantastic deep-dive into modern Angular build systems and managing large-scale open-source monorepos.