Prerequisites

Before the Quickstart, get these on your machine. The list is short and the same everywhere; only how you install them changes by OS.

The short list

Tool	What it’s for
Rust (via rustup)	Compiles the kernel and your app. The per-CPU toolchain (Espressif fork for ESP32, a stock target for RP2040) is added in step 1 of the Quickstart.
make + a POSIX shell (bash)	Drives every build, flash and test. Native on Linux and macOS; on Windows it comes from MSYS2.
Python 3	Build helpers and the RP2040 on-target self-test harness. Standard library only — nothing to pip install.
git	Clone the repository.

Plus the bits for the board you flash. Every board uses the same tools as the rest of its chip family, so this is grouped by family — the two below cover every supported board (see Supported boards for which board is which):

Chip family	To flash	Notes
ESP32 (Xtensa)	espflash + a USB cable	Installed with the toolchain (cargo install espup espflash). Flashes over USB serial.
RP2040 (Arm)	a USB cable + elf2uf2-rs	cargo install elf2uf2-rs. make flash builds a UF2 and copies it over USB — no debug probe needed. If the board already runs FlintOS with USB enabled it enters BOOTSEL on its own (a 1200bps touch); otherwise hold BOOTSEL while plugging in for the first flash.

When you do want a debug probe (RP2040)

A CMSIS-DAP probe with probe-rs is optional — you need it only to run the on-target self-tests (make test-arm-*) or to debug over SWD, not to flash and run your app.

By operating system

Linux

# Debian/Ubuntu; use your distro's equivalent elsewhere
sudo apt install build-essential python3 git
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

build-essential brings make, a C toolchain and bash. For USB access without sudo, add yourself to the serial group (sudo usermod -aG dialout $USER, then re-login) and install probe-rs’s udev rules if you use a debug probe.

macOS

xcode-select --install          # make, git, a C toolchain
brew install python             # or use the system python3
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

macOS ships bash-compatible shells; nothing else is needed for the build system.

Windows

The build is make + shell scripts, so you need Unix tools. MSYS2 provides them — make, bash, the coreutils and cygpath:

pacman -S make          # bash + coreutils come with MSYS2's base install

Add MSYS2’s usr\bin to your PATH so make runs from a normal Command Prompt or PowerShell console, not only the MSYS2 shell. Then install the rest with their native Windows installers:

• Rust — rustup (the MSVC toolchain).
• Python 3 — python.org; tick Add python.exe to PATH.
• git — Git for Windows.

Why MSYS2, and why it just works

The self-test harness runs the same bash scripts as Linux and macOS. A few Windows-only quirks of running native tools under make (path forms, output redirection) are handled inside the scripts, so you don’t have to think about them — you just need make, bash and python on your PATH.

Check it worked

make --version
rustc --version
python --version      # or python3 --version
git --version

Each should print a version. If make or python isn’t found on Windows, your PATH is missing MSYS2’s usr\bin or the Python install directory.

Next

QuickstartBare toolchain to a running board in a few minutes.