{% raw %} Structure your CI workflows to maximize performance and clarity. Each job should have a single, clear responsibility with these guidelines: 1. **One toolchain per job**: Keep jobs focused with a single Rust toolchain version per job. Multiple toolchains in one job create confusion about which version is being used for each command. ```yml # Don't do this: - name: Install Rust stable uses: dtolnay/rust-toolchain@stable with: toolchain: ${{ env.rust_stable }} - name: Install Rust nightly uses: dtolnay/rust-toolchain@stable with: toolchain: ${{ env.rust_nightly }} ``` Instead, create separate jobs for different toolchains or requirements. 2. **Split long-running tasks**: Divide lengthy operations into separate jobs that can run in parallel. When a job begins taking too much time (like Miri tests), split it to enable faster feedback cycles and better resource utilization. 3. **Use efficient testing tools**: Employ optimized testing tools like cargo-nextest to significantly reduce execution time. For example, replacing standard test runners with nextest can reduce CI runtime by 40% or more, as seen with Miri jobs (37 minutes → 21 minutes). These practices will result in more maintainable CI configurations, faster feedback for developers, and clearer error identification when builds fail. {% endraw %}