Japanese software engineers are infamously known for working (usually forced) over time (i.e. forced to take out time card). Because software engineers work over time there is a urban legend that Japanese engineers retire at age 35. However I have to say these often apply only to large general contractors.

Corporate cultural is super rigid and is something you would definitely want to avoid, however I believe this is not always true for startups (especially in Tokyo).

As long as you belong in a English speaking team you should be fine.

Also just be careful of the contract type. Some companies who want to fire workers on the go will try to force some form of a temporary contract.

I heard some horror stories about working in Japan. The country is absolutely astonishing when you visit as a tourist but enduring the rigid traditional culture as a worker is a completely different story.

Perhaps not entirely germane, but I worked for the U.S. branch of a Japanese company - it was about %50/50 Japanese expats and Americas. The Japanese worked 50-60 hours a week, Americans worked in the ballpark of 40 or so, and nobody blinked an eye. They were notoriously stingy on vacation time, which led to a pretty dismal retention rate (partly why that was the only job I left in under a year).

Send patio11 an e-mail. He has previous experience with working 60 hour weeks in Japan.

You get fired.