Build, Flash, and Check

The CLI is intentionally small.

Build

To compile a Flint source file:

flint build --target rp2040 --board pi-pico src/main.fl

For RP2040, this produces a UF2 image that can be copied to the board in BOOTSEL mode.

Run and Flash

The current CLI shape is:

flint run [--target <chip>] [--board <board>] src/main.fl
flint flash --target <chip> build/main.uf2

run is the convenience path for “build and then execute or flash”. flash is the explicit step when you already have an artifact.

Check, Format, and Test

The intended developer loop also includes:

flint test src/
flint fmt src/
flint check --format json src/

These commands matter for Flint’s agent-first goals. A language that wants reliable automated use needs a stable formatter and structured diagnostics, not only a compiler binary.

What This Means In Practice

The shortest description of the workflow is:

1. write a .fl file,
2. target a board or chip,
3. build,
4. flash or run,
5. use diagnostics to correct the program.