Last year I was working on improving the Profile-guided optimization (PGO) workflow used to build the Rust compiler. While doing that, I realized that while PGO works fine for Rust, it is not as straightforward to use and as discoverable as I would have liked. That led me to the creation of cargo-pgo, a Cargo subcommand that makes it easier to optimize Rust binaries with PGO (and BOLT, see below).
