m07-concurrency

What it does: This skill helps decide how to run multiple pieces of Rust code at the same time safely. It explains the difference between work that needs raw computer power (like heavy calculations) and work that mostly waits, like network requests, and recommends different tools for each. It also covers how to safely share data between different running tasks without causing crashes or corrupted data, and how to avoid a situation called a deadlock, where two tasks get stuck waiting on each other forever. When to use it: - Writing code that does several things at once, such as handling many web requests - Fixing errors related to sharing data between threads or async tasks - Deciding whether to use threads, async/await, or message-passing channels - Debugging a program that hangs, freezes, or behaves unpredictably under load This is background guidance automatically used when writing or reviewing concurrent Rust code, not something typed as a direct command.