April 2025 – DUNE/sandreco Summary of work: Delivered foundational capabilities for the GRAIN detector by introducing data structures and processing utilities, establishing the core models needed to represent sparse and dense image data, tracklets, and clusters. Added utilities to count photons and charge from raw SIPM data, laying groundwork for end-to-end GRAIN data processing and analysis. Impact and value: This work creates the structural backbone for future signal extraction, quality metrics, and detector performance insights, enabling faster, more reliable analysis of GRAIN outputs and enabling downstream pipelines to scale with data volume. Major bugs fixed: None reported this month; focus was on building the foundation and preparing the pipeline for future work. Technologies/skills demonstrated: Data modeling for image data (sparse and dense), representation of tracklets and clusters, utility development for sensor data extraction (photon and charge counting), and modular, reusable design geared toward pipeline integration.