I use a TeX version compiled with an ISO Pascal compiler for Windows. The source code is tangled from Knuth's tex.web file and my own change file, plus a small system-specific extension.

This produces DVI files, which I convert to PDF with dvipdfm.

Probably an uncommon set-up.

(I had earlier used javaTeX, but this did not receive Knuth's latest corrections and was much harder to extend.)