Design of complex embedded systems is becoming increasingly expensive, while product life cycles are shortening. Commercial viability requires that silicon platforms get to market quicker and stay in the market longer, making reprogrammability a necessity. We present Cascade, a tool for developing coprocessors that accelerate existing embedded software applications, with no requirement for detailed microprocessor knowledge. Cascade allows functionality to be extended quickly with minimal user intervention, retaining a high degree of reprogrammability of the software implementation thus lengthening the lifespan of the platform and delivering results promptly.