- Coroutines & Scheduler
- Event loop (libuv)
- spawn() / delay() / timeout()
- TaskGroup & TaskSet
- Channels (buffered/unbuffered)
- Future / FutureState
- Pool with CircuitBreaker
- Async File & Pipe I/O
- TCP / UDP sockets
- PDO connection pooling
- FileSystemWatcher
- CURL async
- Deadlock diagnostics
- spawn_thread() — cross-platform OS threads
- Thread lifecycle (request startup/shutdown, TSRM)
- Closure deep copy (op_array transfer via pemalloc)
- Zval transfer between threads (scalars, strings, arrays)
- RemoteException / ThreadTransferException
- Bailout recovery (fatal errors in child threads)
- Object transfer (declared properties)
- Captured variables (use) in closures
- ThreadPool with worker reuse
- ThreadChannel (cross-thread data exchange)
- Thread cancellation
- Test suite & stabilization
- Framework integration layer
- Laravel / Symfony adapters
- Migration guides
- Feature freeze
- Community testing
- Performance benchmarks
- Stable API
- Production ready
- PHP RFC submission