Comment by soapdog
Be aware that Lua doesn't use semver and that versions take many years to be ready. In this page:
https://www.lua.org/versions.html
You can see that between 5.3 and 5.4 there were five years. 5.2 to 5.3 was also a five years gap.
Breaking changes are well documented and we see them years before they happen and nothing requires you to upgrade.
Most code runs on 5.1 forward.