Sly

Based on Emacs's comint.el, it features interactive backreferences that highlight objects and remain stable throughout the session, enhancing code exploration and debugging.

Stickers provide live code annotations that record values as code executes, offering a unique, visual debugging experience not available in SLIME.

Out-of-the-box support for Company, Helm, and other completion UIs using Emacs's completion API, eliminating the need for additional plugins.

Cleanly ASDF-loaded by default, making it straightforward to load contribs and dependencies without manual setup, as highlighted in the README.

Focused on Emacs 24.5+ with liberal use of lexical binding, leading to a cleaner codebase and regular updates, as stated in the fork rationale.