Raw assembly is theoretically portable as well, why do you want the source? My problem with these is that they are cross-platform only as long as the maintaine

Raw assembly is theoretically portable as well, why do you want the source? My problem with these is that they are cross-platform only as long as the maintainers decide they are, you aren't gonna write a vulkan software impl from scratch if the platform doesn't come with one. Now you can argue that this is all very unlikely, but you have to agree that this is no archival. At some point the project will become unusable because of all the automation code it depends on. Binary search will outlive it.