The cffi package is an extension that implements a Foreign Function Interface for Tcl.
The repository for the package is at https://github.com/apnadkarni/tcl-cffi . Current version as of 2022-02-06 is 1.0b4.
Documentation pages are at https://cffi.magicsplat.com .
Source distributions and binary packages for some platforms are at https://sourceforge.net/projects/magicsplat/files/cffi .
See the README for more.