Something got broken between 2014 and 2015 version of texlive-context. Apparently the path configuration is not set correctly. For example: >$ luatools mtxrun | unknown script 'base.lua' or 'mtx-base.lua' >$ context mtxrun | unknown script 'context.lua' or 'mtx-context.lua' Reproducible: Always
you need to run 'mtxrun --generate' as the user that will use context; the elog message was outdated (telling to use luatools --generate); I've just updated it