Interviewing well is part of your job.

Let me say that again:

Interviewing well is part of your job.

You are not a good developer if you don't interview well, because by not interviewing well you just deprived that company of your skills. Now that code is worse. And it's your fault. Had you done your job (interviewing) properly, that code would be better.

It's part of your job to show people how good you are. It's sales, yes. You know your product (you) very well and know how it would help the customer. So make sure you get that message across. Go read some books about sales.

Get good at interviewing.