A minimalist clone of Acme.
From the README:
"ma" is a minimalistic clone of the acme[1] editor used in Plan 9, and is written in Tcl/Tk?. It has been tested with Tcl/Tk? 8.5, mostly under Linux and OpenBSD. "ma" has successfully been run on Mac OS X with XQuartz, but needs a tiling window manager to be used in a satisfactory way.
Available at: https://www.call-with-current-continuation.org/ma/ma.html