Concurrency model

This hub maps the main concurrency building blocks in C++ and how they fit together. Use it to navigate from low-level thread primitives to async results and coroutine-based flows. Keep the model simple: execution units, shared state, synchronization edges, and completion channels.

# Mental Model Diagram

Key idea: execution units communicate through shared state; synchronization defines visibility/order; futures/promises carry completion and result transfer.

# Execution Units

• Thread support library
• std::thread
• std::jthread
• Coroutines

# Synchronization Primitives

• std::mutex
• std::condition_variable
• std::latch
• std::barrier

# Atomics and Ordering

• Atomics overview
• std::memory_order
• std::atomic_thread_fence

# Async Results and Cancellation

• std::future
• std::promise
• std::stop_token

# Fast Entry Points

• Base primitives: Thread support library
• Shared-state ordering: Atomics overview
• Async composition: std::future
• Suspension model: Coroutines