The Spring system is a highly integrated collection of software and hardwar
e that synergistically operates to provide end-to-end support in building c
omplex real-time applications. In this paper, we show how Spring's specific
ation language, programming language, software generation system, and opera
ting system kernel are applied to build a flexible manufacturing testbed. T
he same ingredients have also been used to realize a predictable version of
a robot pick and place application used in industry. These applications ar
e good examples of complex real-time systems that require flexibility. The
goal of this paper is to demonstrate the integrated nature of the system an
d the benefits of integration; in particular, the use of reflective informa
tion and the value of function and time composition. The lessons learned fr
om these applications and the project as a whole are also presented.