GitHub - davidmonterocrespo24/velxio: Emulate Arduino, ESP32 & Raspberry Pi. in your browser. Write code, compile, and run on 19 real boards — Arduino Uno, ESP32, ESP32-C3, Raspberry Pi Pico, Raspberr

Velxio is a fully local, open-source browser-based emulator for 19 embedded boards including Arduino Uno, ESP32 variants, Raspberry Pi Pico, and Raspberry Pi 3B. It supports 5 CPU architectures (AVR8, ARM Cortex-M0+, RISC-V, Xtensa LX6/LX7, ARM Cortex-A53) using avr8js, rp2040js, custom RISC-V TypeScript, and QEMU backends. Users can write Arduino C++ or Python in a Monaco editor, compile via arduino-cli, and simulate with 48+ interactive electronic components including LEDs, displays, sensors, and more. Features include a wire system with signal-type color coding, serial monitor, library manager, multi-board simulation on the same canvas, and project persistence with auth. Self-hosting is available via Docker. Licensed under AGPLv3 with a commercial option.