Velxio 2.0 – Emulate Arduino, ESP32, and Raspberry Pi 3 in the Browser

Summary

Velxio: Arduino & Embedded Board Emulator Live at velxio.dev A fully local, open-source multi-board emulator. Write Arduino C++ or Python, compile it, and simulate it with real CPU emulation and 48+ interactive electronic components — all running in your browser. 19 boards · 5 CPU architectures: AVR8 (ATmega / ATtiny), ARM Cortex-M0+ (RP2040), RISC-V RV32IMC/EC (ESP32-C3 / CH32V003), Xtensa LX6/LX7 (ESP32 / ESP32-S3 via QEMU), and ARM Cortex-A53 (Raspberry Pi 3 Linux via QEMU). Velxio is free and open-source. Building and maintaining a full multi-board emulator takes a lot of time — if it saves you time or you enjoy the project, sponsoring me directly helps keep development going. Your support helps cover server costs, library maintenance, and frees up time to add new boards, components, and features. Thank you! https://velxio.dev — no installation needed. Open the editor, write your sketch, and simulate directly in the browser. To self-host with Docker (single command): docker run -d -p 3080:80 ghcr.io/davidmonterocrespo24/velxio:master Then open http://localhost:3080. Raspberry Pi Pico simulation — ADC read test with two potentiometers, Serial Monitor showing live output, and compilation console at the bottom. Arduino Uno driving an ILI9341 240×320 TFT display via SPI — rendering a real-time graphics demo using Adafruit_GFX + Adafruit_ILI9341. Library Manager loads the full Arduino library index on open — browse and install libraries without typing first. Component Picker showing 48 available components with visual previews, search, and category filters. Multi-board simulation — Raspberry Pi 3 and Arduino running simultaneously on the same canvas, connected via serial. Mix different architectures in a single circuit. ESP32 simulation with an HC-SR04 ultrasonic distance sensor — real Xtensa emulation via QEMU with trigger/echo GPIO timing. Raspberry Pi Pico Raspberry Pi Pico W ESP32 DevKit C ESP32-S3 ESP32-C3 Seeed XIAO ESP32-C3 ESP32-C3 SuperMini ESP32-CAM Seeed X...