Show HN: Esp32sim – Run ESP32 firmware in the browser

Esp32sim is a Rust-based ESP32 emulator that runs actual ESP32 firmware in a web browser using WebAssembly, supporting multiple ESP32 variants (ESP32, S3, C3, C6) with instruction-level emulation across both Xtensa and RISC-V architectures. The emulator boots real ROM, bootloaders, and unmodified application images with sufficient hardware modeling to run real projects, including features like GPIO, UART, displays, and virtual networking. It operates at 150-240 million instructions per second—well above real-time speeds—and requires no cloud accounts or patched firmware.