Largest Rust codebases



I was wondering what are the largest Rust codebases known at this point?

I’m interested in applications or frameworks written in Rust that solve an external domain problem - like Firefox Quantum or the Linkerd service mesh, I’m NOT interested in tools or libraries written in Rust that are used by the Rust ecosystem (the compiler, build tools, analyzers etc.).

I’ve started looking at the links on the “Friends of Rust” page, but I wanted to know if any relatively big projects are known at this point.

Many thanks!


The largest Rust codebase I can think of off the top of my head is Servo. It had around 5 million lines when I last ran cloc against it. Quantum’s codebase was either derived from or is directly from a sub project within Servo.


I think Servo is the largest, and Parity, an Ethereum implementation, is the next. Currently Parity includes 198753 lines of Rust in 817 files. (Average 243 lines per file.)

Note that Servo repository includes web-platform-tests which is not in Rust. Ignoring tests, I get 370387 lines of Rust in 957 files. (Average 387 lines per file.)


Thanks @rustdev and @sanxiyn for the replies and the clarification on the Servo repository size.

Indeed, there’s quite a difference between 5 million and 370k loc.


Rust itself is pretty large too. 550K lines of code.

Within other large opensource project would probably be

  • Redox (if you include everything), although they did a great job keeping the kernel small
  • TiKV (around 80k loc)


Great suggestions!


Using loc to count, Rusoto has more than 720k lines of Rust code. :grinning: Not sure if that fits into “external domain problem” constraint, though.