I was cleaning up my tectonic plate and fault algorithm and got frustrated with several parts of it so I decided to redo much of it. That involved going all the way back to the Voronoi code and fixing a couple of longstanding bugs, improving and generalizing some floodfill/breadth-first-search functions and rasterization functions, and reimplementing the way faults create terrain.
The first benefit is that I now have coastal shelves. Hopefully all my other fault features like ocean ridges and subduction mountain ranges will also look better.