`3. Social. Common Lisp is boring technology: widely used across application domains and platforms, well understood, warts included. There are decent to good libraries for many things I want to use but not make my specialty. No Scheme implementation comes close to that. Racket probably has the best library support, but it still pales compared to Common Lisp. Platform support is another point: I can use Common Lisp on all my computing devices (including in particular my Android e-ink tablet).

`1. Historical. I had adopted Common Lisp as my main Lisp before even thinking about this project, so CLOG played no role in the decision. I had been using Racket intensively for a few years, and then discovered Smalltalk, which I have also used intensively for a few years. I had learned to appreciate the language malleability of Racket and the interactivity and introspection of Smalltalk. So I ended up adopting Common Lisp as the middle ground: it has both of these features in imperfect but usable form.