Writing in C introduces whole families of vulnerability that aren't a problem in most other languages. Format string vulnerabilities and buffer overflows are the two that immediately come to mind, and these will be added to the normal host of web application security considerations like SQLI, CSRF, XSS, etc.
What followed the phase in which you were writing everything in C?
It's only been recently that I have started sitting down with projects and thinking, which language makes sense here?
I've been through these phases too. But they keep on recurring time after time. I've been writing everything in C, then C++, then Haskell, then back to C and this has been going on for years.
Well at least both Haskell and C have good educational value, so even if it is a bit odd, you're still learning valuable skills.
Me too. As I get older, though (I'm well past "maturity" ;), I find myself going back to C more and more. I'm not exactly sure why.
I do think, though, that while our discussions of programming languages nearly always revolve around this or that feature making things easier, or more efficient, or more fault-tolerant, or whatever, there's also an element of "intellectual fun" (or something like that).
I won't say I never get aggravated writing C, but I often enjoy the puzzles that emerge. Trying to figure out how to do something in C, trying to visualize what's going on with the memory, creating clever little pointer-machines -- it's just as fun as doing analogous things with Lisp or Haskell (during one's obligatory Lisp and Haskell phases).
I've gone back to writing most things in C. Including web apps. If you're a crappy programmer, the "new hip" languages might protect you from some classes of issues, but the idea that you're "safer" is deeply, deeply misguided.