AFAIK, mailman was the only thing ever wrapped in this way.

I wrote all the rest of the back-office utilities (at least, the initial versions of them), and I have never come across any indication that they got "wrapped" in anything else (they did, no doubt, evolve and mutate in something utterly different over time).

Yegge's quote is also slightly inaccurate in that mailman, like all early amzn software, was written in C++. Shel and I just chose not use very much of the (rather limited) palette of C++ syntax & semantics.