# Mach Performance Improvements

**URL:** <https://discourse.mozilla.org/t/mach-performance-improvements/147617>\
**Category:** Firefox Tooling Announcements\
**Created:** [March 13, 2026, 8:22pm UTC](https://discourse.mozilla.org/t/mach-performance-improvements/147617 "2026-03-13T20:22:28Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![ahochheiden](https://sea1.discourse-cdn.com/flex001/user_avatar/discourse.mozilla.org/ahochheiden/32/72011_2.png) [@ahochheiden](https://discourse.mozilla.org/u/ahochheiden)\
**Post date:** [March 13, 2026, 8:22pm UTC](https://discourse.mozilla.org/t/mach-performance-improvements/147617/1 "2026-03-13T20:22:28Z")

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Hi all, I wanted to share some of the performance optimizations for `mach` that have landed recently or are landing soon:

- [bug 1775197](https://bugzilla.mozilla.org/show_bug.cgi?id=1775197) reduced the overhead of `mach`’s initialization process by ~30%-50% (highly platform and command specific), which means that commands you invoke could begin executing up to a second sooner than before, which should make things feel much more responsive.

- [bug 2018327](https://bugzilla.mozilla.org/show_bug.cgi?id=2018327) sped up a pre-test step that verifies all test files are in the right place before tests start running. On Windows, this shaved ~13 seconds off the time between invoking `./mach test`/`./mach xpcshell-test` and tests actually starting to run (~75% speedup). Minor (if any) improvement on Linux/macOS.

- [bug 2017746](https://bugzilla.mozilla.org/show_bug.cgi?id=2017746) (landing today) speeds up `./mach configure` by adding caching to a `taskcluster` step that verifies you have up-to-date toolchains, which saves up to 10 seconds (~50% speedup) if none of the toolchain input files changed since the previous run. The most common scenario that benefits from this is editing your `mozconfig` then building.