Here is a raw dump of the TeX program. Eventually I will try to make it easier to read, cross-reference against corresponding code sections in other versions/programs, etc.
Please see previous page for some ways you can prepare to read this. In particular, taking a look at these programs may help:
Note: This page takes a long time to load fully, and may download about 60 megabytes.To read the program, click on "Fetch modules" below.