Disappointing as this article has an inappropriate title, it contains nothing relevant to a "bank".
The first and second posts are here
http://www.pitheringabout.com/?p=693
http://www.pitheringabout.com/?p=749
Tangentially, the 'swedish colleague' the author brought in to help with the transition to Clojure is the immensely talented Hakan Raberg (sorry don't know how to type umlauts etc on my keyboard) , who is a good friend and worked with me at ThoughtWorks before he went indie.
It was a nice read. I liked the frankness - no claims to overnight Ninjitsu mastery - and yet I get the feeling it's all pretty solid.