Features

Display scaling without changing your desktop Pick the size of X windows independent of the rest of the desktop. macXserver windows scale on their own.
Scalable Mac fonts through core X11 Every X font request maps to a Core Text font at integer pointSize. No bitmap catalog on disk, no client-side Xft setup, no compile flags. Just the standard core X11 font path with scalable Mac fonts on the other end. Anti-aliased throughout.
X windows are first-class macOS windows One NSWindow per X top-level. Real Mission Control behavior. Optional Motif-style window frame when you want it.
Session capture and replay Capture-first was the methodology for the whole project. The framer and proxy were Day 1, before a single opcode handler. Every byte of every session can be recorded to a .xtap file and replayed against another server.
Remote app launcher One click from the Mac status menu to an X client running on a vintage Sun. Passwords in Keychain, optional verbose progress, two-stage menu grouped by host.
Shaped windows: oclock, xeyes, and friends Round windows and oval windows that stay round at Retina device scale. The SHAPE mask gets traced to a CGPath and rasterized at the window's actual backing resolution, so the edges of oclock and xeyes don't stairstep. The Motif frame plays along.
Built-in resource editor with themes Edit the X RESOURCE_MANAGER from inside macXserver. Theme switching, line-numbered code editor, reload without restart.
Map X font names to Mac fonts X clients ask for fonts by classic names like 'fixed' or 'helvetica'. macXserver maps each one to a real Mac font. The mapping is user-editable and lives in a single small file.