This article presents a case study of using a constraint programming solver in a system level synthesis framework called SYLVA. The solver is used to find the repetition vector of a synchronous data flow graph and serving as the design space exploration engine, which rapidly finds qualified system implementations by solving a constraint satisfaction optimization problem. Each system implementation is a combination of a number of function implementation instances and their cycle accurate execution schedules. The problem to be solved is automatically generated based on the user inputs: 1) a system model to be synthesized, 2) a library containing all the usable function implementations, 3) the performance/cost constraints, and 4) the optimization objectives. Use of constraints programming technique enabled a low cost development of design space exploration engine in addition to gaining ease of use.