Design of real-time MPSoC systems including multiple appli-cations is challenging because temporal requirements of each applicationmust be respected throughout the entire design flow. Currently the de-sign of different applications is often interdependent, making converge toa solution for each application difficult. This paper proposes a composi-tional method to design applications independently, and then to executethem without interference. We define a formal modeling framework as asuitable entry point for application design. The models are executable,which enables early detection of specification errors, and include the for-mal properties of the applications based on well-defined models of com-putation. We combine this with a predictable MPSoC platform templatethat has a supporting design flow but lacks a simulation front-end. Thestructure and behavior of the application models are exported to an in-termediate format via introspection which is iteratively adapted for thebackend flow. We identify the problems arising in this adaptation andprovide appropriate solutions. The design flow is demonstrated by a sys-tem consisting of two streaming applications where less than half of thedesign time is dedicated to operating on the integrated system model.