Researchers are increasingly using high performance computing (HPC), including GPGPUs and clusters, for computational and data-enabled science and engineering (CoDeSE) applications. Unfortunately, HPC software developers must solve reliability, availability, and maintainability problems at extreme scales, consider reproducibility, understand domain specific constraints, deal with uncertainties inherent in scientific exploration, and develop algorithms that use computing resources efficiently. Software engineering (SE) researchers have developed tools and practices to support development tasks, including: requirements management, design, validation and verification, testing (unit and system), continuous integration, and maintenance. HPC CoDeSE software requires appropriately tailored SE tools/methods. The SE-CoDeSE workshop addresses this need by bringing together members of the SE and HPC communities to share perspectives and present findings from research and practice (both successes and failures), and to generate an agenda to improve tools and practices for developing HPC software. This workshop builds on the success of 2013-2016 editions of similar workshops.