Project is in platform.io folder. Open this and dependencies should auto-install. This uses ESP-IDF not Arduino framework.
The example ESP32 board is the M5Stack Gray.
No external PSRAM or flash needed. Build is about 800K
A message file is loaded in Messages.c so you need an SD Card supported. Pinout might be different from the M5Stack in which case change the definitions in main.c
It is probably possible to build the messages file into the code. This is left as an exercise for the user.
I've run a pub/sub test here on it running on an ESP32 for a few hours and it seems quite reliable
WiFi STA settings are also in main.c and will need changing. There's no clever provisioning in place atm
Project is in platform.io folder. Open this and dependencies should auto-install. This uses ESP-IDF not Arduino framework.