Famously Ars Digita, founded by Philip Greenspun, started out using AOLserver and Tcl to design websites. The company wrote what I suppose would now be called a "middleware stack".

After he sold the company to Red Hat I worked there really briefly. Apparently half the sales fell through because Tcl wasn't regarded as "enterprisey" enough for customers (note the customers themselves would probably never write a line of code). There was an attempt to rewrite the entire engine in Java — it being 2002 — which limped along for a while before the project died.

But there's more! The original Tcl stack was open sourced and continues to this day as OpenACS (https://openacs.org/).

The Java rewrite also still exists (https://svnlegacy.ow2.org/byline/) but has been dead 15+ years, and just digging into those 7 level deep directories rekindles a feeling of dread in me.