@yogthos I find low-level projects like GCC, Linux, & GDB are good examples of this. I've heard that Linus Torvalds or Richard Stallman first wrote these they only worked on a specific CPU architecture.
Now they've been totally rearchitected to work on any CPU architecture.
Feel free to debate if this is the best way to organize the programming effort, but it sure makes it more straightforward to install an OS.
For people who care about, support, or build Free, Libre, and Open Source Software (FLOSS).