In this chapter we argue that an intelligent program development environment that proactively supports the user helps a mainstream programmer to overcome the difficulties of programming multicore computing systems. We propose a programming environment based on intelligent software agents that enables users to work at a high level of abstraction while automating low-level implementation activities. The programming environment supports program composition in a model-driven development fashion using parallel building blocks and proactively assists the user during major phases of program development and performance tuning. We highlight the potential benefits of using such a programming environment with usage scenarios. An experiment with a parallel building block on a Sun UltraSPARC T2 Plus processor shows how the system may assist the programmer in achieving performance improvements.