It will affect you as much as you let it - meaning if you stress over phone interviews, in person interviews, meetings, etc - then it will definitely bother you. However, I think you'll be pleasantly surprised with the personalities of other software engineers. I have a pretty bad block, I tend to block for 3-5 secs on one or two words in each sentence. And I've never had anyone mock me, or call it out, etc. They are very forgiving and genuinely want to hear whatever it is you are trying to say. As for tips, maybe disclose it off the top? During an interview the first time you have a bad stutter or bad block, just say "by the way - I have a stutter" and continue on with whatever it is you were saying. I've done this a few times and I've never seen the interviewer blink an eye, they don't care.