- The mp4 metadata parser. This has been shipping for a while now, and was the first shipped Rust code. - The URL parser (rust-url). This is not shipping, beca

- The mp4 metadata parser. This has been shipping for a while now, and was the first shipped Rust code. - The URL parser (rust-url). This is not shipping, because it's incomplete and there are some mismatches to deal with. But it exists. - Stylo: Servo's CSS engine in Firefox. By far the biggest one, this is shipping in beta and nightly, and should be there in the 57 release for everything but Android - webrender: Servo's GPU-focused renderer. Not shipping, can be flipped on in nightly. Still has work to be done - encoding-rs: All encoding operations go through this now. Shipping - The U2F stuff: A lot of the U2F code is in Rust. Shipping in nightly though I think it's still off by default (but that will change soon?) As far as the location of the code: The root rust crate is at https://hg.mozilla.org/mozilla-central/file/tip/toolkit/library/rust https://hg.mozilla.org/mozilla-central/file/tip/toolkit/libr... . Everything can be reached from it, and the cargo file that has all these links is https://hg.mozilla.org/mozilla-central/file/tip/toolkit/library/rust/shared/Cargo.toml https://hg.mozilla.org/mozilla-central/file/tip/toolkit/libr... - All of Servo is vendored in tree in https://hg.mozilla.org/mozilla-central/file/tip/servo https://hg.mozilla.org/mozilla-central/file/tip/servo . Not all of Servo is used, the majority of the used code is from https://hg.mozilla.org/mozilla-central/file/tip/servo/components/style https://hg.mozilla.org/mozilla-central/file/tip/servo/compon... - Webrender is vendored in tree in https://hg.mozilla.org/mozilla-central/file/tip/gfx/webrender https://hg.mozilla.org/mozilla-central/file/tip/gfx/webrende... - The U2F HID stuff is vendored at https://hg.mozilla.org/mozilla-central/file/tip/dom/webauthn/u2f-hid-rs https://hg.mozilla.org/mozilla-central/file/tip/dom/webauthn... - There's a bunch of stuff in libcubeb ; I don't even know what it's there for (https://hg.mozilla.org/mozilla-central/file/tip/media/libcubeb https://hg.mozilla.org/mozilla-central/file/tip/media/libcub...) - You can find "c api" rust crates scattered throughout, like mp4parse_capi, rust-url-capi, encoding_glue . These depend on the actual crate (usually, a crate that's published to crates.io) but expose an API that C can call into - Finally, any dependency from crates.io is vendored in https://hg.mozilla.org/mozilla-central/file/tip/third_party/rust https://hg.mozilla.org/mozilla-central/file/tip/third_party/... . Note that this includes build time dependencies (so you'll find crates that deal with CLI parsing and terminal color info that aren't actually used by firefox). Despite the folder being labeled "third_party", a lot of that code is maintained by us, but in separate repos and published to crates.io. In particular, large chunks of Servo are reusable published crates.