LIRC

LIRC is the piece of software that decodes the IR signal signals received from your remote and that encodes and sends the IR signal to your devices. It has only a command line interface (CLI) but in the d-diot image you can find a nice web interface (lirc_web) that makes your life easier. Of course LIRC and lirc_web are integrated in Home Assistant.

The IR receiver (TSOP4838) and the IR blaster, a 3W 940nm IR LED, are integrated in the d-diot board.

See the following guides to known more.