I am not the author, but I write most of my grad-student research-project-quality code in CL. Here are some things I have experienced so far: 1. Pure dynamic

I am not the author, but I write most of my grad-student research-project-quality code in CL. Here are some things I have experienced so far: 1. Pure dynamic typing is a headache. I use type hints quite frequently, tend to use defstruct rather than cons, etc. SBCL has a pretty good type inference system and gives very useful compile-time feedback about types. 2. Macros can help improve organization and code re-use when used properly. Macros can also turn code into an unreadable mess when used improperly. The only way to learn what is "proper" is experience / practice; books like On Lisp and Let over Lambda help but you really do need to get your hands dirty. 3. Debugging across an FFI is really painful. The debugging tools for Lisp are fantastic, the debugging tools for C are fantastic, but those tools compose poorly. 4. I wish the standard allowed map, reduce, and similar constructs to be defined for arbitrary sequence types. There is more to life than lists and arrays. 5. I wish the standard came with more useful data structures. Associative lists in CL are great if you never have more than a tiny number of items in them; an associative tree type would be a great addition. It would also be nice to have a standard priority queue type, a standard random-access list type, etc. 6. Performance is easy to underestimate. SBCL does a bang-up job of optimizing code, with a few exceptions. The optimizer in SBCL could use some work, of course, but it is nowhere near as bad as people seem to expect for a high-level language. Overall, I think what CL is desperately in need of is an updated standard. The world has changed a lot since CLtL2; we need a CLtL3. There are a lot of non-standard libraries that are widely used and that should just be standardized -- MOP, generic sequences, an FFI, etc.