---
url: https://mikrojs.dev/develop.md
description: Contribute drivers, board packages, and firmware to Mikro.js
---

# Development Guide

This section covers building Mikro.js firmware from source, writing drivers for sensors and peripherals, shipping C/C++ with a package as a native module, and describing development boards as board packages.

## What you can contribute

* **Drivers**: code for a sensor, display, motor controller or other peripheral. A driver is JavaScript on the core APIs, or a native module when it needs C or C++.
* **Native modules**: C/C++ that a package ships, compiled into the firmware and imported by its package specifier.
* **Board packages**: prebuilt firmware for a development board, and optionally the board's pin names and drivers wired to its pins.
* **Core runtime**: Bug fixes, performance improvements, and new platform APIs in `packages/@mikrojs/native/`.

## Prerequisites

* [Node.js](https://nodejs.org/) >= 24
* [pnpm](https://pnpm.io/) >= 10.30
* [direnv](https://direnv.net/) (loads the repo's `.envrc`, so the `mikro` CLI runs from source)
* ESP-IDF prerequisites for your platform: see [Espressif's setup guide](https://docs.espressif.com/projects/esp-idf/en/stable/esp32/get-started/linux-macos-setup.html)
* A USB cable and an ESP32 development board (for on-device testing)

## Getting the source

```sh
git clone --recurse-submodules https://github.com/mikrojs/mikro.git
cd mikro
pnpm install
```

If you already cloned without submodules:

```sh
git submodule update --init --recursive
pnpm install
```

This installs all workspace dependencies and builds the `qjsc` bytecode compiler (used during firmware builds).

## What's next

* [Custom Firmware](./custom-firmware): build and distribute custom firmware from npm packages
* [Building from Source](./building-firmware): set up ESP-IDF and build firmware from the monorepo
* [Creating Drivers](./creating-drivers): write a driver for a peripheral in JavaScript
* [Native Modules](./native-modules): ship C/C++ with a package, compiled into the firmware
* [Creating Boards](./creating-boards): define a board package with pin maps and sdkconfig
* [Architecture](./architecture): how the build system, module registration, and bytecode pipeline work