This page is automatically generated using this tool by MiniDigger: Spigot Resolver
If the page is outdated go nag MiniDigger or just update it yourself using that tool
This page contains all versions of spigot you can build using buildtools (java -jar BuildTools.jar --rev <version>), together with the nms and bukkit (maven) version and links to the sources on stash for that version.
Be sure to checkout the thread too here
1.8 and 1.9? Look at this page
1.10 up? Look at this page
1.16 and up? Look at this page