A VPN (Virtual Private Network) is a way of securely connecting to your home network without exposing it to the world.
FLAC and Opus are audio formats. FLAC uses lossless compression and offers the best uncompressed quality while not being as huge as a broadcast wave (.wav) file. Opus is similar to an mp3, that means it is a lossy compression, but it sounds extremely good at small bit rates/with bad connections. The transcoding-on-the-fly-bit means the user opens up the private Navidrome website running in their home from the road and the Audio they play is compressed and sent over on the fly as they play it.
Self hosting sounds scary, but it is an essential skill nowadays and extremely useful. Things I self-host (besides websites) include a partskeeper instance which is essentially a stock keeping system for electronics parts, jellyfin as a netflix replacement for films and series, my mailserver (mailcow), paperless-ngx (hooked up to a scanner, allows automatic text-recognition and tagging of invoices, letters, etc.) and homeassistant (smart home).
That probably makes it appear like I have to spend all my free time on this, but it takes surprisingly little of my time to maintain this, with a lot of it running on a single Raspberry Pi.
Sure, it is really easy to maintain… if you are already skilled with system administration and how all of these things work.
> use NordVPN Meshnet to securely connect to them outside of the home
> host an entire FLAC library and then transcode to Opus on the fly.
i really have no idea what any of these words mean. Spotify's future is secure.