Maintaining and improving the existing, implementing, and researching new exploit mitigations for the Rust compiler

Define compiler intermediate representation usable by external tools

Refactoring the trait system of rustc

Improving the binary size of Rust programs and libraries

Improving rustc compilation performance (build times)

Soundly expanding the capabilities of compile-time function evaluation in Rust

Providing users with a great experience when debugging Rust code

Aiming to make rustc better at telling the user why the compiler isn't smart enough to understand their code yet

libgccjit AOT codegen for rustc

Improving incremental compilation in rustc

Working with LLVM upstream to represent Rust in its development

Revival and Improving the Rust Macros

Writing MIR optimizations and refactoring the MIR to be more optimizable

Making parallel compilation the default for rustc

Working on an experimental new borrow-checker implementation

Implementing polymorphization to reduce unnecessary monomorphisation in rustc

Triaging bugs, mainly deciding if bugs are critical (potential release blockers) or not

Making the compiler easier to learn by maintaining and improving the Rustc Dev Guide

Helping new and experienced contributors learn more about rustc

Improving the -Z self-profile feature of the Rust compiler