If it’s C or C++, I get the source from the project’s GitHub / GitLab / Source Hosting thing and compile it for myself.
For programming languages that I don’t read, I usually use the AUR.
Also,
- GoG for games
- Xilinx website, for that one time, I got the ISE
- AppImage sometimes
Gatekeeping the word “software” here?
Here’s something not in the AUR. Tested on arch