Built-in facilities and interoperability

Operation contracts state what they consume or borrow, whether they allocate or block, and what remains after failure.

• Built-in types and operations: numbers, text, tuples, lists, dictionaries, sets, and ranges.
• Input, output, and files: arguments, streams, whole-file helpers, and owned file handles.
• Concurrency and parallelism: certified workers, ownership transfer, channels, pools, cancellation, and bounded waits.
• C interoperability: trusted imports, text and ownership adapters, library exports, metadata, and runtime loading.

These APIs follow the ownership and error/allocation rules. They need no import; modules that do are in the standard library.