Hello,
compiling a LuaLaTeX document with rev. 20998 of expl3 results in the error:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!
! This is a LaTeX bug: check coding!
!
! Command `\lua_shipout_x:n' not yet defined!
!
! See the LaTeX3 documentation for further information.
! For immediate help type H <return>.
!...............................................
l.68 \cs_generate_variant:Nn \lua_shipout_x:n
{ x }
in the file l3luatex.sty; probably because \latelua is not enabled by default.
Regards,
Philipp