I still find good old manpages really useful for coding, their long lifetime made them reliable and well integrated into a lot of tools (vim in my case). What’s more satisfying than accessing the exact doc you’re looking for in a couple of keystrokes? It’s hard to go back to browsing HTML docs after that…
Imagine the sadness when Khronos stopped supporting the vulkan API manpages! Long story short, I tried to add the support upstream (see PR #839), ended up keeping an unofficial fork and released something usable there (formatting is still weird sometimes).
As usual, the source code is available on GitHub. There’s also a vulkan-man-git package on AUR if you’re using Arch Linux.