Velxio Lets You Simulate Raspberry Pi, Arduino, and ESP32 Boards in Your Browser

Simulate Before You Solder

The hardware prototyping workflow has always carried a costly step: you have to physically own the board to test your code on it. Cloud-based simulators like Wokwi have reduced that barrier for common platforms, but they carry tradeoffs — cloud dependency, privacy concerns for proprietary projects, and limited hardware coverage beyond the most popular boards.

Velxio, released April 4, 2026 and covered by CNX Software, addresses all three with an approach that is simple in concept and impressive in execution: a fully self-hostable, open-source board emulator that runs entirely in your browser with no cloud backend required.

19 Boards Across 5 CPU Architectures

The hardware coverage is the first thing that stands out. Velxio supports 19 real boards across five distinct CPU architectures:

- **AVR8** — Arduino Uno and Nano, the ATmega328P-based classics every maker knows

- **Xtensa / QEMU ESP32** — ESP32 and ESP8266 for IoT and wireless projects

- **RISC-V** — emerging open-architecture MCU boards for developers evaluating the platform

- **RP2040** — Raspberry Pi Pico and Pico W

- **Raspberry Pi 3 (Linux)** — full Linux SBC simulation with GPIO behavior

This breadth means Velxio is useful not just for Arduino prototyping but for evaluating RISC-V boards before purchasing hardware, testing RP2040 firmware, or simulating Raspberry Pi GPIO behavior without a physical board on your desk.

48 Wirable Components and Dual Language Support

The component library is equally practical: 48 virtual components including LEDs, resistors, capacitors, buttons, displays, sensors, and motors can be wired to the simulated board using a graphical breadboard interface. Both Arduino C++ and MicroPython are supported for code execution.

The simulation engine runs actual firmware execution within the browser — not a simplified emulation that approximates behavior, but a proper CPU-architecture emulator that executes your code as the real hardware would.

Self-Hosted Via Docker

The self-hosting story is where Velxio genuinely differentiates. A single Docker pull-and-run command launches the full stack locally, making the simulator available at localhost:3000 — no external network traffic, no cloud API calls, no data leaving your environment. For teams working on proprietary hardware projects or educational institutions with data governance requirements, this is a meaningful architectural advantage over cloud-hosted alternatives.

Licensing and Availability

Velxio is licensed under AGPLv3 and free for personal and educational use. The source code is publicly available on GitHub. Commercial licensing is available for organizations deploying Velxio in production environments without the AGPLv3 copyleft requirements.

For makers, electronics educators, and firmware developers who want a private, self-contained simulation environment, Velxio is a well-timed addition to the open-source hardware toolchain.

Sources: CNX Software (April 4, 2026), Velxio GitHub (2026)