Pretty much. The whole thing (including scripts, packages, configuration, etc.) is written in CL, there's no C core (minus a bit of ffi here and there for e.g. shell interaction). This makes it really easy to modify the editor's source code while you're in it. Another bonus of everything being written in a general-purpose language like CL is that you can leverage any random CL library for your config/packages, and don't have to do janky stuff like lsp-bridge calling Python in order to have non-blocking completion.
Besides better defaults, it supports multithreading and launches instantly, feeling a lot snappier all-around. When I first started using lem, I basically just used it as a shell editor for non-code stuff like text/config files, since it started much faster than emacs (I don't like using the daemon) and had the same keybinds. At some point I started using common lisp for a personal project and it's become my main editor since. Development is also super active.
Besides better defaults, it supports multithreading and launches instantly, feeling a lot snappier all-around. When I first started using lem, I basically just used it as a shell editor for non-code stuff like text/config files, since it started much faster than emacs (I don't like using the daemon) and had the same keybinds. At some point I started using common lisp for a personal project and it's become my main editor since. Development is also super active.