Sure, but, at least in my experience, new hires are ALWAYS on probation. So to me the status quo is this: you get vetted "harshly" in the interview process, then you have to clear the probation period. That said, I think it's pretty much a given you clear the probation period if you don't clash with coworkers, and write decent code. During your first ~90 days, you're ramping up, learning the company's procedures and coding conventions (and code base itself), and getting to know your coworkers... so I think the only time probation really bites you is if it's a bad fit culturally (which I would think you're at higher risk for the smaller the company - those startups are selective as hell about who they hire).