> So, if one isn't careful, it's possible to write a very clean, very nice Lisp DSL which is totally incomprehensible to anybody but the author, and thus hell t

> So, if one isn't careful, it's possible to write a very clean, very nice Lisp DSL which is totally incomprehensible to anybody but the author, and thus hell to maintain over time. You can't really call it a "very nice" DSL if it is incomprehensible and unmaintainable :) What you have described is one issue, but it really doesn't have a lot to do with lisp DSLs. You can make that mistake in any language. A problem that is more specific to lisps is that since it really is possible to write beautiful programs, there is a temptation to spend a lot of time designing DSLs or otherwise refactoring your program to make it very clear, concise and maintainable - but without actually making it more useful. You may spend hours (or weeks) improving your code without actually improving functionality at all. This is less of a temptation in Java, for example, because it's such a rubbish language to program in in the first place there's very little temptation to spend time refining your code. You just accept that your program is never going to feel like a work of art no matter what you do, and get on with actually producing a useful solution.