The Xiph.org foundation maintains FLAC and they have a list of tools that might be helpful. Source: about 1 year ago

Lastly, ALAC hasn't been updated by apple since 2016. FLAC is actively maintained by xiph.org and saw its last update this past October. Source: over 1 year ago

Excessive licensing costs weren’t the only concern surrounding MQA though. MQA is touted as being DRM free, with audio streams able to be stored in the very popular, open source FLAC format. Only the lower resolution 16-bit audio is truly DRM free however. MQA’s authentication watermarking must be present in the file, and properly validated at playback, otherwise MQA decoders will refuse to unfold the audio to... Source: over 1 year ago

FLAC continues to be actively maintained and updated. Which, actually thanks for asking your question because in checking sources I noticed FLAC was just updated not two weeks ago. I thik the last time I updated my encoder libraries was after MP3 lost patent protection and dropped licensing a few years ago, so this is fortuitous timing! Anyways, FLAC continues to be meaningfully updated (homepage @ xiph and the... Source: over 1 year ago

There are lossless audio compression standards such as FLAC. Source: almost 3 years ago

This isn't really Chromecast - it's 'raspicast' and needs it's own app. There are tons of similarly titled howtos that make it sound like you can run your own chromecast server -- you can't, unless you buy an expensive thing from airserver.com or a cheap chromecast. I have yet to find any real opensource chromecast server. Source: over 1 year ago

On Windows and Mac, there's Airserver - https://airserver.com. Source: over 1 year ago