[lmm]

It's rarely "just" a port. It's usually because the new language has better characteristics. These days porting can be a very gradual, as-needed process - partly because of thrift, another Facebook tool!

One of the big parts of becoming a professional for me was accepting that code has a lifecycle; code is written to make the business money at the time, but it's entirely normal for it to change and die as time goes on.

(That said, you should just write everything in Haskell and then you won't have these problems. When was the last time you saw a company port code away from Haskell?)