The document proposes a framework for building a successful developer ecosystem for multi-sided platforms. It suggests platforms must balance developer needs and platform strategy. The framework maps developer needs on the y-axis and platform strategy on the x-axis. Key design elements for developer needs include API model, rewards, development environment, and support. Platform strategy elements include platform model, control, governance, and addressing multi-homing and network effects. The document outlines these elements and surveys developers on needs.