Zoo Management System (ZMS) is a self-developed modular platform designed to digitalise small-/medium-sized institutions, tested using a zoological facility. It combines automated climate control, animal data management, time tracking and resource planning. It was developed entirely independently using low-cost hard- and open-source software. The platform is easy to expand, customisable and significantly more affordable than commercial off-the-shelf systems. It aims to reduce administrative effort, simplify operations and improve animal care without licenses. A central user interface presents all functions to the user, running on all platforms. The system integrates seamlessly into daily routines and is specifically tailored to the requirements and constraints of non-profit organisations.