In XF assembler. Once built (which can take a moment or two), you have a very basic, unpatched MVS 3.8 BSP system. Good enough to move from that to a mainframetastic, fully patched, AI-age ready MVS 3.8 with all kinds of added systems! Yeah!
Does it work? Yes.
Oh wait, the macro library is included, too!
enjoy!
January 2025
PS: You can find the XF assembler to build this source at: https://github.com/moshix/IFOX. ...
... but then you would need another, earlier assembler to assemble XF, which in turn means you would need...my brain is fried.
May 2026, Elektrostaal