That's a good question. The honest answer is that we didn't. By the time we made this decision it was far more about convincing developers. The history of getting to that point is one of trying small experiments with new tech and proving that we make good decisions and can be trusted.
We did have a big meeting with all of R&D where we talked about all the pros and cons. Hiring was a big question early on although it's still my belief that using Clojure rather than Java is a positive in terms of attracting good programmers. I don't think we have enough data to answer that either way though.
I think that most important part was that we weren't betting the whole company on it. We were only betting a few weeks of developer time. If it didn't work out then the worst case was rewriting those services back into Java (in fact until recently we had a single Scala service from a previous experiment). Quite a few companies start off by writing some internal tooling in Clojure as an easy to stomach first step. That may be a good path if management are resistant.
We did have a big meeting with all of R&D where we talked about all the pros and cons. Hiring was a big question early on although it's still my belief that using Clojure rather than Java is a positive in terms of attracting good programmers. I don't think we have enough data to answer that either way though.
I think that most important part was that we weren't betting the whole company on it. We were only betting a few weeks of developer time. If it didn't work out then the worst case was rewriting those services back into Java (in fact until recently we had a single Scala service from a previous experiment). Quite a few companies start off by writing some internal tooling in Clojure as an easy to stomach first step. That may be a good path if management are resistant.