[marwis]

There were plenty of those, including commercial ones.

It's pretty hard to find but ~25 years ago I was using Xi Graphics Accelerated-X which had 3D acceleration long before Xfree86.

Update: but yes I imagine it had some code from original MIT release.

For completely independent one you can have a look at WeirdX/WiredX, which was written in Java and even supported antialiasing and transparency for core protocol (something that Xfree86 people claimed to be impossible to implement).

It's surprisingly hard to find this stuff today: https://web.archive.org/web/20250220140358/http://www.jcraft...

[the_why_of_y]

Oh, WeirdX, that's one I hadn't heard of.

The commercial ones (Xsun, Xsgi, Hummingbird, DESQView/X etc.) were all based on MIT code.