We give an overview the progress of our work in silicon photonic programmable circuits, covering the techn stack from the photonic chip over the driver electronics, packaging technologies all the way to the sof layers. On the photonic side, we show our recent results in large-scale silicon photonic circuits with diff tuning technologies, including heaters, MEMS and liquid crystals, and their respective electronic driving sch We look into the scaling potential of these different technologies as the number of tunable elements in a ci increases. Finally, we elaborate on the software routines for routing and filter synthesis to enable the pho programmer.