Patrick Maier, Phil Trinder Implementing a High-level Distributed-Memory Parallel Haskell in Haskell ABSTRACT: We present the initial design, implementation and preliminary evaluation of a new distributed-memory parallel Haskell, HdpH. The language is a shallowly embedded parallel extension of Haskell that supports high-level semi-explicit parallelism, is scalable, and has the potential for fault tolerance. The HdpH implementation is designed for maintainability without compromising performance too severely. To provide maintainability the implementation is modular and layered and, crucially, coded in vanilla Concurrent Haskell. Initial performance results are promising for three simple data parallel or divide-and-conquer programs, e.g., an absolute speedup of 135 on 168 cores of a Beowulf cluster. KEYWORDS: parallel functional programming, implementation.