Mocktastic: A Meshtastic Node on Arduino

Mocktastic is an educational, experimental C++ client that demonstrates building and decoding Meshtastic-compatible LoRa packets on ESP32 hardware; it is not a fork of the official firmware. It targets the LilyGO T3 LoRa32 V1.6.1, combining an ESP32-PICO with an SX1276 radio, and is intended to be adapted to other compatible boards. The firmware has two compile-time modes: DECODER, an interactive serial shell for receiving, decoding, and sending channel messages and direct messages; and SENSOR, which reads temperature and humidity from a DHT22 and returns measurements when prompted with “/dht” on a configured private channel. Its code covers packet handling, protobuf payloads, encryption, radio operations, and shell parsing.

Using the project requires setting board-specific LoRa pins, choosing a regionally permitted radio frequency and matching preset, and configuring channel and node credentials in keys.h. The decoder shell supports public and private messages, direct messaging after exchanging a public key, and commands for RSSI, radio settings, and testing. The sensor requires a DHT22 on GPIO 21 and a battery for standalone use. Portable protocol and utility logic is separated from hardware-dependent code, allowing host-side doctest tests to cover helpers, cryptography, packet processing, and command parsing with “make test”; radio and sensor behavior must still be checked on-device. The layout and extension guidance point developers to the shell parser and dispatcher for adding commands, and to the packet interfaces for broader protocol changes.