HiFiBerryOS is our version of a minimal Linux distribution optimized for audio playback. The goal isn't to add as much functionality as possible, but to keep it small. Therefore, it is based on Buildroot and it's not possible to use package managers to add more software.
There is a robust update mechanism that will not overwrite the system, but switch between the current and the new version (they run on different partitions). This is documented in more detail at doc/updater.md.
The user interface is based on the Bang & Olufsen Beocreate project.
At the moment, the following services are supported:
Spotify (using a fork of Spotifyd) - requires a paid Spotify subscription
Airplay (using shairport)
Squeezebox (using squeezelite)
Bluetooth A2DP sink (using BlueZ 5)
Roon - requires a Roon subscription
MPD
Snapcast (experimental, using Snapcast and SnapcastMPRIS)
Analogue input on DAC+ ADC with input detection (using a custom alsaloop implementation)
Webradio (experimental)
Additional tools that are available:
sox
HiFiBerry dsptoolkit
There are several ways to add functionalities to HiFiBerryOS or integrate it into other systems.
The main backend controller application is called audiocontrol and offers an API that can be used to start/stop players, switch sources or retrieve metadata. This is often the easiest way if you want to integrate it into other systems, e.g. a automation system.
Audiocontrol provides a plugin system that can be used to add more complex integrations.Also have a look at the "Anatomy of a controller plugin"
HiFiBerryOS is based on buildroot. This means, you can't easily install additional software from command line. Even if you do, it will be gone after the next update as an update will replace the full filesystem. You need to integrate additonal software via the Buildroot build system
The UI also uses a plugin concept. Plugins are called extensions. Have a look at the Beocreate documentation
You can find technical documentation in the repository's doc folder
The documentation for building images from source can be found here
We're looking forward to your contributions. Depending on functionality and code quality, we will decide if a contribution will be included in the base system or will be provided as a user-contributed module that users need to install by themselve.