SRON, Netherlands Institute for Space Research, is developing a Focal Plane Assembly for future missions requiring large-format arrays of Transition Edge Sensors. The up-scaling of the amount of pixels together with the mass and volume limitations for a space instrument requires technology developments in several areas. A dedicated program has been initiated to develop the required magnetic shielding, high density electrical interconnects and a thermal insulating suspension. The purpose of the program is to demonstrate Technology Readiness Level 4-5 for these key-technologies before the end of 2015. In this talk we will present the status of the program, as carried out under ESA GSTP.