After a few years of hacking with Clojure, and before that Erlang, Python, and JavaScript, I decided to dig into Common Lisp. This was a few months ago, and I have some questions for the Common Lisp experts out there in 2017.

When I’ve tried to improve products I’ve worked on, I’ve found it helpful to hear from relative newcomers despite the fact they don’t seem to understand how things are supposed to be done. I’m hoping this list of questions might serve a similar purpose for members of the Common Lisp community.


  • Why don’t libraries have version numbers?
  • Why is adding libraries to Quicklisp a manual process that requires human review? Is there an alternative non-curated registry?
  • Why aren’t ASDF dependencies automatically fetched if missing?
  • Why do so few libraries use GitHub?

Open source

  • Are there serious open source efforts to modernize documentation?
  • Are there serious open source efforts to modernize libraries?
  • Are there efforts to encourage open source contributions?
  • My apologies, but I’d never even heard of GitLab prior to seeing all these libraries hosted on Why not GitHub?


  • Why hasn’t the open source community standardized on a single implementation, i.e. SBCL?
  • Would there be any benefit to extending SBCL beyond the Common Lisp standard to better support modern language features and paradigms?

Functional programming

  • Why aren’t there more libraries using a functional, immutable paradigm? Most seem to use many dynamic variables and large functions spanning multiple screens, with variables mutating throughout
  • Are there any functional programming advocates in the Common Lisp open source community?


  • Are there any efforts to bring innovative libraries from the Clojure (or elsewhere) community into Common Lisp?
  • Is there software design innovation occurring in the Common Lisp community or is the community primarily focused on maintenance and tuning?
  • Is it worth the time and energy to develop new libraries to modernize Common Lisp – or perhaps a single extended implementation of it, like SBCL – or would that time and energy be more productively spent in a non-Common Lisp community?


  • Why is on-boarding new developers so difficult? For instance, why isn’t Roswell linked to from every About Common Lisp page?
  • Why hasn’t the Common Lisp Foundation updated the home page since 2015?


  • Why are there so few instructional or advocacy bloggers?
  • Why can’t Google search find many good resources? I.e. a search for “Common Lisp” is not that helpful.

Quick advice for newcomers

  • See /r/lisp sidebar for good learning resources
  • Use Roswell to install and switch between implementations of Common Lisp, like SBCL and CCL
  • Emacs Slime or Atom Slime, take your pick
  • See Quickdocs for popular curated libraries
  • ALL CAPS doesn’t mean the compiler or documentation is mad at you, it’s just a bit hard of hearing after all these years

Update, August 14, 2017

This post generated a large number of very informative and thoughtful replies from the community on Reddit, for which I’m grateful.

I’m also grateful to phoe for compiling the answers in a more pleasing format. See his Answers from 2017 Common Lisp experts (mirror).

"Be kind whenever possible. It is always possible." -- Dalai Lama
"The true sign of intelligence is not knowledge but imagination." -- A. Einstein