This is TexiWeb Jr., a super simple literate programming system built
on top of Texinfo and implemented in awk.
The "tangle" piece was successfully bootstrapped on November 4, 2013.
The "weave" piece started producing a reasonable-looking document
on November 11, 2013.
As of Fri Feb 19 12:07:09 IST 2016, both the source code and literate programming document
are licensed under the GNU GPL. See the file COPYING.
Other repositories from the same author are interesting too: e.g.
the portable C compiler
https://github.com/arnoldrobbins/pcc-revived
and a converter from RCS to git
https://github.com/arnoldrobbins/simple-rcs2git