Cargo considers Rust versions for dependency version selection 1.84.0 stabilizes the minimum supported Rust version (MSRV) aware resolver, which prefers dependency versions compatible with the project’s declared MSRV. With MSRV-aware version selection, the toil is reduced for maintainers to support older toolchains by not needing to manually select older versions for each dependency.
You can opt-in to the MSRV-aware resolver via .cargo/config.toml:
[resolver] incompatible-rust-versions = "fallback" Then when adding a dependency:
$ cargo add clap Updating crates.io index warning: ignoring clap@4.5.23 (which requires rustc 1.74) to maintain demo's rust-version of 1.60 Adding clap v4.0.32 to dependencies Updating crates.io index Locking 33 packages to latest Rust 1.60 compatible versions Adding clap v4.0.32 (available: v4.5.23, requires Rust 1.74) When verifying the latest dependencies in CI, you can override this:
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