The biggest programs I've worked on are way smaller than 1MLOC, but I've dug around a few large code-bases written in dynamic languages(emacs most notably, 1M l

The biggest programs I've worked on are way smaller than 1MLOC, but I've dug around a few large code-bases written in dynamic languages(emacs most notably, 1M lines of Lisp, 1/4M lines of C), and my unproven theory of large systems is that it might be a good idea to make mistakes have smaller impact, rather than try to avoid them(they are inevitable), by focusing on better abstractions, and thus keeping problems more local, focusing on the protocols rather than on the implementation. Static typing might help here, but designing a protocol/interface/api/dsl is hard and I need to experiment a lot with it, so I'm willing to sacrifice some safety for better overall design and flexibility(which will hopefully make debugging easier). IOW I agree you need DSLs, polymorphism and all that good jazz. Where my disagreement comes in is that It's a trade off, and not necessarily an absolute need to have a lot of static typing. In my personal work I'm willing to make the trade off and work with clay rather than marble. Other people work and think differently and I accept that; absolute truths are rare in computer science, and don't exist in software engineering, its all trade-offs here :) ps My hobby vaporware CL project will probably be called mudball, I'm trying to learn how to design systems with hackability and extreme flexibility in mind :)