Engineering Effectiveness Newsletter (June 2023 Edition)

Welcome to the June edition of the Engineering Effectiveness Newsletter! The Engineering Effectiveness org makes it easy to develop, test and release Mozilla software at scale. See below for some highlights, then read on for more detailed info!



Detailed Project Updates

Bugzilla and Bugbug

Build System and Mach Environment

CI and Treeherder

  • Andrew Halberstadt created mozilla-taskgraph and landed a VPN change to use it. This provides a place to add shared Taskgraph code across projects that doesn’t quite belong in the core Taskgraph repo
  • Andrew Halberstadt continued moving projects (app-services, vpn, gecko) away from the multi_dep loader in favor of Taskgraph’s from_deps transforms. This is a nice useability improvement for Taskgraph developers in these projects.

Crash Management

Lint, Static Analysis and Code Coverage

OS Integration and Security


  • Calixte Denizet added the possibility to edit already existing text annotations
  • Calixte Denizet improved the rendering of some annotations in HCM
  • Rob Wu published a new version of the addon for Chrome
  • Jonas Jenwald fixed some bugs and improved the overall quality of the code.

Firefox Translations

  • In preparation for release, Greg Tatum fixed performance and memory regressions for enabling Firefox Translations and fixed accessibility blockers for the new UI.
  • Erik Nordin has been adding Telemetry for translations, fixed a performance regression caused by language identification, and fixed detection for unsupported CPUs.
  • Ben Hearsum has completed the initial work on porting the Firefox Translations training pipeline to Taskcluster. We are now able to run the full pipeline, and will be able to begin training new language models in the next few weeks.

Power use

Release Engineering and Management

  • [FFXP-2366] Heitor Neiva and the RelEng team landed MacOS notarization on linux; Moving it away from hardware macs to k8s, making it scalable and easier to maintain. It also opens the door to potentially move code signing MacOS builds to linux as well.
  • Ben Hearsum and Nick Alexander doubled the number of attributed Firefox downloads on Windows. This means, we are able to tell where users downloaded Firefox from in 50+% of the cases. Before then, attribution was lower than 25%.
  • Heitor Neiva set up the ESR115 repository (metabug 1835641). Firefox 115.0esr will ship on July 4th.
  • Windows 7/8 and macOS < 10.14 deprecation: Geoff Brown implemented the channel switch for these deprecated OSes. Release users will be migrated to 115.0esr later in July. Beta channel migration was started on July 4th.
  • Julien Cristau fixed a bug that prevented Sheriffs from adding new jobs/retriggering them on the firefox-android repos (taskgraph#267)

Version Control


  • Isabel Rios Escobar, Aaron Train, Heitor Neiva and Nishant Bhasin have enabled physical device testing on CI for iOS projects for the first time.
    In order to get there, we have deployed a solution that integrates the iOS CI system, Bitrise, with Firebase. We have changed the test application configuration to sign it properly so that we can generate a valid IPA file that can be installed in Firebase’s physical devices. This allows us to run the Robo tests which are meant to crawl the application randomly searching for crashes.
  • Zeid Zabaneh add more telemetry to mozregression and released a user survey. These feed into planning future mozregression improvements.

Thanks for reading and see you next month!