DescriptionThis paper introduces ALPINE, a flyweight in situ infrastructure. The infrastructure is designed for leading-edge supercomputers, and has support for both distributed-memory and shared-memory parallelism. It can take advantage of computing power on both conventional CPU architectures and on many-core architectures such as NVIDIA GPUs or the Intel Xeon Phi. Further, it has a flexible design that supports for integration of new visualization and analysis routines and libraries. The paper describes ALPINE's interface choices and architecture, and also reports on initial experiments performed using the infrastructure.