Like many others commenting here, I too use SBCL because of its good performance. I keep CLISP around mainly for nostalgia's sake. I began learning Common Lisp in Sep 2007 during a long layover at an airport using CLISP 2.41 on Debian 4.0 (Etch). Also, having another implementation helps me to test that my code is portable and does not rely on any SBCL-specific features.
Swank/Slynk clients are generally preferable to LSP clients when doing Common Lisp. LSP infrastructure in Lisp (notably, the cl-lsp library) is relatively young and not widely used, whereas Slime/Swank is thoroughly battle-tested because it has been widely used years before LSP has been created.
As a side note, this also means that Lisp programmers have been enjoying the functionality nowadays provided by LSP decades before it started being cool. :D
I know about Smalltalk, but I didn't know about Java and .NET! Could you point me to utilities for those languages that allowed for features like autocompletions, introspection, live debugging, recompilation, REPLs - standard stuff in Slime/Swank?
autocompletions have been a feature in IDEs since Visual C++ was introduced, and copied by Java IDEs, and naturally Visual Studio for .NET languages as well.
Introspection, graphical code navigation has been a thing in Apple MPW, Borland C++ for Windows, Visual Age for C++ (latter CSet++), C++ Builder, Eclipse, Visual Cafe, Visual Studio Enterprise.
Live debugging and recompilation, edit-and-continue in Visual Studio, JVM class reload capabilities and JRebel JVM agents.
REPLs, available as standard feature in Java since Java 9, prior to that there were IDE features like Eclipse Scrappages. Visual Basic interactive mode (classical VB), and nowadays F#, C# and VB.NET interactive shells on VS, including send-to-repl capability.
Lucid Energize C++ tooling from 1993 already enjoyed some of these features:
Yeah, due to dynamic types is might do well than C++/C#/Java refactoring tools.
However the first refactoring tools appeared on Smalltalk, which is also a dynamic language, but it doesn't have macros and the image provides metadata that Lisps don't always have available.
This is what I've been using to learn CL. It's a very small barrier to entry compared to when I've tried (and failed) in the past to approach Lisp from Emacs.
* Recommendations on learning Common Lisp: https://news.ycombinator.com/item?id=25442155
* On Lisp communities on Reddit r/lisp and Freenode #lisp: https://news.ycombinator.com/item?id=25543565
* Observations on State of Common Lisp Survey 2020: https://news.ycombinator.com/item?id=25291780
* Lisp in Vim with Slimv/Vlime: https://news.ycombinator.com/item?id=21735148
* Emacs4CL (a tiny quick starter ~/.emacs): https://news.ycombinator.com/item?id=25440690
Like many others commenting here, I too use SBCL because of its good performance. I keep CLISP around mainly for nostalgia's sake. I began learning Common Lisp in Sep 2007 during a long layover at an airport using CLISP 2.41 on Debian 4.0 (Etch). Also, having another implementation helps me to test that my code is portable and does not rely on any SBCL-specific features.