Deployment and reconfiguration are two important development stages in wireless sensor network (WSN). Currently, the main challenges of the WSN development include the constrained platform resources, the complicated application development process as well as the unstable wireless communications. In this paper, we present our sensor node platform iLive which is equipped with the AVR 8-bit microcontroller ATmega1281. To address the challenge of iLive's high memory resource constraint, a resource-efficient event-driven operating system is designed and applied. As for the simplification of user application development process, an efficient and user-friendly middleware is implemented. Moreover, the wireless communication quality in large-scaled WSN is also improved by several effective mechanisms. Through the one-year practical experiment, it has been verified that iLive is a platform which can afford the fundamental WSN tasks in both the smart home and the precise agriculture application domains.