NextGen In A Box (NGIAB): Open-Source containerization of the NextGen framework to enable community-driven hydrology modeling

The NextGen Water Resources Modeling Framework (NextGen) greatly increases the flexibility and interoperability of hydrologic modeling workflows. However, deploying NextGen models remains challenging due to a complex installation process. To address this, we developed NextGen In A Box (NGIAB), an all-in-one distribution of the NextGen framework that simplifies deployment across environments using Docker and Singularity containers. NGIAB comes pre-configured with most components expected in version 4.0 of the National Water Model, which will use the NextGen framework. Additionally, NGIAB utilizes a cloud-based continuous integration/continuous deployment pipeline to automate releases. Through its ease of access and robust suite of included utilities, NGIAB promotes community engagement in hydrologic modeling and facilitates research-to-operation (R2O) pathways. In this work, we present the designs and technologies that enable these outcomes, along with studies and performance benchmarks that demonstrate NGIAB’s applicability. • NGIAB streamlines deployment via an open-source containerization of the NextGen framework. • Full reproducibility across local, cloud, and HPC environments. • CI/CD automation enables long-term development and maintenance. • Provides end-to-end workflow for developing and running NextGen-based models. • Accelerates Research to Operations transitions for community hydrology research models.