This is like a telemarketer asking what's the best way to sell their life insurance policy when interrupting someone's dinner. The problem is that there is a general lack of empathy in almost all of these 'introductions'. I already know there's a lot of developer jobs out there. So what are you accomplishing by emailing me, other than spamming me that the companies you represent are also hiring? How it is going to help my career to leave my current position and join yours? Are you going to give me new experience in an interesting field? Let me lead a critical project? Pay me more money?

Telling me what VCs have invested, how 'fast-paced' the company is, how 'work-hard-play-hard' you are is pretty much irrelevant to me, other than I guess the somewhat desperate sounding angle that your equity will be worth a lot. Usually the reason you can't answer the questions I asked above is because you don't have a good answer to them - you are just trying to spam me by 'selling' a mediocre product with no differentiating advantages. So you're just spamming me, so don't send the email. If you can't answer the question of why it will be great for my career, past OMG WE'RE DEFINITELY THE NEXT FACEBOOK or WE HAVE MICROBREWS AND UNDEFINED VACATION POLICY, then you're just a telemarketer/spammer and there's no sane advice to give you other then don't click send. Keep it on the job board and out of people's inboxes.