The brains of the MIDI Goblin hardware is nothing more than an esp32 microcontroller. Its powered through the esp32’s USB-C connector. The MIDI Goblin can also be flashed through the USB-C connection using the arduino IDE. And the serial output can also be monitored in the Arduino IDE as well when the MIDI Goblin is plugged in and the appropriate port has been selected - Its pretty darn handy.

Other than that - MIDI Goblin uses 5 pin midi din connectors to connect to synths and MIDI controllers.

Now I know what you’re thinking: Why no MIDI over usb? Why not take advantage of the esp32’s built-in WIFI and Bluetooth? Why would you make such a limited device? The answer: simplicity. There’s quite a lot of things that can be done with 5 pin midi connectors, many many synths use them and I personally just find it easier to work with some limitations imposed.