- the additional work that needs to be done in order to be able to go on a holiday - opposite of backlog.
I am going on holidays Friday and have all this frontlog of work I need to get finished by Thursday afternoon.
Comes from the word of "backlog". frontlog is typically used as a verb to indicate that you're going to do things sooner than later, even sooner than necessary. That way they are done, and out of the way.
Let's frontlog this work because we know we're going to require several iterations before we get it right, so we dont' want to wait for the last minute to start.