mcujs
JavaScript runtime for microcontrollers
Drop an index.js onto your Pico, open the REPL, and iterate fast. Think of it as Node for tiny boards: familiar JavaScript, instant feedback, and a modular runtime under the hood.
Drag-and-drop scriptsREPL over USBRP2040 + RP2350
mcujs v0.1.0 on pico
> GPIO.init(25, GPIO.OUTPUT)
> setInterval(() => GPIO.toggle(25), 500)
> console.log('Blinking!')
Blinking!
Quick start workflow
Flash a UF2, mount the drive, add index.js, and reset. No toolchain needed for most users.
Runtime basics
Learn the REPL commands, module loading, and filesystem behavior that make iteration quick.
Explore the runtimeHardware APIs
GPIO, PWM, I2C, SPI, and ADC are available as built-in modules. Expand support as new boards come online.
Browse APIs