This bundle contains two packages, ctablestack and luatexbase. Both are designed to augument the LuaTeX support provided by the LaTeX kernel (and available in plain as ltluatex.tex). The ctablestack package provides the concept of a push/pop stack for category code tables. The luatexbase package emulates an older package of the same name, most of which has been directly incorporated into the kernel but where small (interface) segments are now deprecated but still required to be available as code is modified to use the new interfaces.