About Tcl and the embedded world, a few years ago I wrote a single-file Tcl interpreter that is mostly compatible with current Tcl implementations (something is missing like namespaces, something was added like anonymous functions):

http://jim.tcl.tk/index.html/doc/www/www/index.html (source code is here: https://github.com/msteveb/jimtcl)

Now maintained by Steve Bennett, and actively used by some embedded folks.