cargo-msrv

Find minimum supported Rust version

$ cargo msrv find

$ cargo msrv find --linear

$ cargo msrv verify

$ cargo msrv show

$ cargo msrv set [1.56.0]

$ cargo msrv list

$ cargo msrv --path [/path/to/project] find

cargo msrv [options] command

cargo msrv finds and manages the Minimum Supported Rust Version (MSRV) for Rust projects. It determines the oldest Rust compiler version that can successfully build a crate by testing against available toolchains. By default it uses binary search to efficiently narrow down the compatible version range.
Maintaining an accurate MSRV is important for library authors who want to support users on older Rust versions. The tool can automatically set the `rust-version` field in Cargo.toml after finding the minimum version, and verify that the declared MSRV remains valid as the codebase evolves.

--path dir

Project directory path

Use linear search instead of binary

Minimum version to consider

Maximum version to consider

Target platform

Path to Cargo.toml

find

Discover the MSRV by testing versions

Check if project works with declared MSRV

Display MSRV from Cargo.toml

Update rust-version in Cargo.toml

Show MSRVs of dependencies

Requires rustup for toolchain management.

Binary search is much faster than linear (79+ minor versions exist). Set MSRV via package.rust-version field in Cargo.toml.

cargo(1), rustup(1)