Ardour

I use mostly hardware, but Ardour for the mastering.

I use https://guitarix.org/ on an old laptop for all my preamp effects on guitar.

I occasionally make MIDI covers, so I use Rosegarden for actually transcribing MIDI songs and Sonic Visualizer to figure out the exact notes used in the original tracks. I've also messed around with Reaper, FL Studio and various music trackers (SunVox, MilkyTracker etc)

If you play guitar, you might like tuxguitar for doing guitar notation. It does both music sheets and tabs

SuperCollider, LilyPond, ffmpeg, Ardour

Pure data is one i like to use

A friend of mine produces her music with lmms. She plays guitar and then adds drums and other instruments in lmms and arranges them I guess. https://lmms.io/

rm mostly:)

I'm not much of a musician, but I've used MilkyTracker for some chiptune work

Sometimes Ardour. I use a neural amp modeller made by the guitarix dev (can't remember if this is the exact name) along with files from tone3000. LSP plugins, Vital synth, and a bunch of other plugins. I've been looking at opendaw which recently added tone3000 support which is pretty cool but it didn't really replace bitwig for me, interesting tool for collabs though.