Research shows there are three keys to building muscle: muscle tension, metabolic stress, and muscle damage. While traditional training will take care of the first two, nothing creates that growth-inducing damage like eccentric (negative) work.
After your normal pull-ups and rows, finish your lats off with 3 sets of 3-5 reps of eccentric front levers.
Make sure you can control the lowering phase. If you can't control your decent, just tuck one or both knees in a bit and slowly progress them out over time.