# forge.jit.jit

```python
forge.jit.jit(func: Any = None, /, **options: Any) -> Any
```

Compile a plain function over arrays and numbers with numba.

Write ``@fg.jit`` or ``@fg.jit(fastmath=True)``. The first call compiles the function, which
takes a second or more. Arrays read from ``d`` are read only, so a jitted function cannot
write into them. ``fastmath`` is the only option: Forge runs sweeps in parallel itself, and
compiles each run's code fresh.

Since Forge API 1.