Backstory

So right now I'm working on a story that has tons and tons of backstory. But backstory can be the kiss of death. Nothing slows the pacing like stopping the forward progression of the narrative to shoehorn in something that happened a long time ago. So this was my revelation about backstory:

Backstory should be like a striptease. You reveal just enough to make the reader want more. Then, when they're nearly frantic with their desire to know what happened, you can reveal all. Ideally, it should be at a moment when the backstory intersects in a dramatic way with the main plot.