Getting reviews

Thorough code reviews are one of Mozilla’s ways of ensuring code quality. Every patch must be reviewed by the module owner of the code, or one of their designated peers.

Commit message syntax

When submitting your commit(s), use the following syntax to request review for your patch:

Request	Syntax	Description
Single reviewer	r=reviewer	Request a review from a single reviewer (reviewer). Historically, the syntax r?reviewer requested a review, and r=reviewer marked the reviewer who accepted the patch before landing. Both can now be used interchangeably when requesting a review.
Multiple reviewers	r=reviewer1,reviewer2	Request reviews from both reviewer1 and reviewer2.
Blocking review	r=reviewer!	Request a blocking review from reviewer. This means that reviewer must review the patch before it can be landed.
Both optional and blocking reviews	r=reviewer1,reviewer2!	Request a blocking review from reviewer2, and an optional review from reviewer1.
Review groups	r=#review-group	Request a review from members of #review-group. A full list can be found below.
Blocking review groups	r=#review-group!	Request a blocking review from a review group. This will require at least one member of the group to approve before landing.

For example, the commit syntax to request review from group group-name or developer-nickname would be:

Bug xxxx - explain what you are doing and why r?#group-name

or

Bug xxxx - explain what you are doing and why r?developer-nickname

Reviews, and review groups, can be selected or adjusted after submission in the phabricator UI.

Sometimes when publishing a patch, groups will automatically be added as blocking reviewers due to the code being touched. In this case, you may want to check that the reviewers you requested review from are set to blocking as well.

Choosing reviewers

• If you have a mentor assigned on the bug you are fixing, the mentor can usually either also review or find a suitable reviewer on your behalf.

• If you do not have a mentor, see if your code fits into one of the review groups below, and request review from that group.

• Otherwise, try looking at the history of the file to see who has modified it recently. (For example, hg log <modified-file> or git log <modified-file>)

• Finally if you are still unable to identify someone, try asking in the #introduction channel on Matrix.

Getting attention

Generally most reviews will happen within roughly a week. If, however, a reviewer doesn’t respond within a week or so of the review request:

• Contact the reviewer directly (either via e-mail or on Matrix).

• Join developers on Mozilla’s Matrix server, and ask if anyone knows why a review may be delayed. Please link to the bug too.

• If the review is still not addressed, mail the reviewer directly, asking if/when they’ll have time to review the patch, or might otherwise be able to review it.

Remember that reviewers are human too, and may have complex reasons that prevent them from reviewing your patch in a timely manner. Be confident in reaching out to your reviewer, but be mindful of the Mozilla Community Participation Guidelines while doing so.

For simple documentation changes, reviews are not required.

For more information about the review process, see the Code Review FAQ.

Review groups

Name	Owns	Members
#anti-tracking	Core: Anti-Tracking	Member list
#build or #firefox-build-system-reviewers	The configure & build system	Member list
#cookies	Core: Cookies	Member list
#cubeb-reviewers	cubeb, Gecko’s audio input/output library and associated projects (audioipc, cubeb-rs, rust cubeb backends)	Member list
#desktop-theme-reviewers	User interface CSS	Member list
#devtools-reviewers	Firefox DevTools	Member list
#dom-worker-reviewers	DOM Workers	Member list
#dom-storage-reviewers	DOM Storage	Member list
#fluent-reviewers	Fluent (FTL) files (translation).	Member list
#firefox-source-docs-reviewers	Documentation files and its build	Member list
#firefox-ux-team	User experience (UX)	Member list
#firefox-svg-reviewers	SVG-related changes	Member list
#frontend-codestyle-reviewers	ESLint, Prettier or Stylelint configurations.	Member list
#android-reviewers	Fenix, Focus and Android Components.	Member list
#geckoview-reviewers	GeckoView	Member list
#gfx-reviewers	Graphics code	Member list
#intermittent-reviewers	Test manifest changes	Member list
#layout-reviewers	Layout	Member list
#linter-reviewers	tools/lint/*	Member list
#mac-reviewers	Mac-specific code	Member list
#media-playback-reviewers	Media playback	Member list
#mozbase	Mozbase	Member list
#mozbase-rust	Mozbase in Rust	Member list
#necko-reviewers	network code (aka necko, aka netwerk)	Member list
#nss-reviewers	Network Security Services (NSS)	Member list
#perftest-reviewers	Perf Tests	Member list
#permissions or #permissions-reviewers	Permissions	Member list
#places-reviewers	Bookmarks & History (Places)	Member list
#platform-i18n-reviewers	Platform Internationalization	Member list
#preferences-reviewers	Firefox for Desktop Preferences (Options) user interface	Member list
#remote-debugging-reviewers	Remote Debugging UI & tools	Member list
#search-reviewers	Search	Member list
#sessionstore or #sessionstore-reviewers	Firefox: Session Restore	Member list
#spidermonkey-reviewers	SpiderMonkey JS/Wasm Engine	Member list
#static-analysis-reviewers	Static Analysis	Member list
#style or #firefox-style-system-reviewers	Firefox style system (servo, layout/style).	Member list
#supply-chain-reviewers	Third-party audits and vendoring (cargo-vet, supply_chain).	Member list
#tabbrowser or #tabbrowser-reviewers	Firefox: Tabbed Browser	Member list
#theme or #desktop-theme-reviewers	Firefox: Theme and Toolkit: Themes	Member list
#urlbar-reviewers	Urlbar (Address Bar)	Member list
#webcompat-reviewers	System addons maintained by the Web Compatibility team	Member list
#webdriver-reviewers	Marionette and geckodriver (including MozBase Rust), and Remote Protocol with WebDriver BiDi, and CDP.	Member list
#webgpu-reviewers	WebGPU code	Member list
#webidl	WebIDL	Member list
#xpcom-reviewers	XPCOM	Member list

To create a new group, fill a new bug in Conduit::Administration. See bug 1613306 as example.