I am shortly going to move from a large, multinational, enterprise software house to a start up where I will be the only full time developer. I've worked in start ups and in companies where there have been only three or four devs before so I'm fairly happy with many of the differences in general company feel. But having never worked as a sole dev there a couple things I've got used to in a large company that I think will take more adjustment. And was wondering if there was any advice on how to manage them?
If there are lots of scientists there you might be in luck. Scientists are generally curious and capable of logical reasoning, so you should be able to use them to some extent for code reviews. Simply show the code to one of them and explain to her how it works. This will not be a very formal review, but most of the time simply trying to explain your code to someone else makes you see the problems. In fact, explaining your code to a non-programmer might actually be more effective for noticing flaws.
And given that the scientists must be involved with whatever it is you are writing, and given that they are generally capable of logical reasoning, they may give you some constructive feedback.
As far as geeking out, this may work too. Scientists are geeks too, they just use a different lingo. And they tend to be knowledgeable in technical matters. You may not be able to discuss the finer points of C++ with them easily, but you should be able to find common topics to randomly natter about.
It sounds like you will be wearing multiple IT hats. You may become the DBA, the internal IT, as well as the network admin.
As for what to do about having a relationship with another "computer geek", if you don't find it at the new company then you can always have your IT-outlet on the many online forums (this one included).