GDSFactory is an open-source Python library for generating GDS layouts of photonic circuits, analog devices, quantum components, MEMS, PCBs, and 3D-printable objects. It supports design creation via Python functions or YAML, along with verification tools including design rule checking, layout-versus-schematic checks, simulations, and automated lab testing. The library uses function-based components with decorators like @cell for unique naming based on parameters, geometry operations such as boolean AND/OR/XOR, and netlist extraction for circuit simulation. GDSFactory+ provides real-time file change tracking, automatic component rebuilding, and error monitoring. Joaquin Matres presented the tool in talks on its end-to-end workflow from design to fabrication. The project is hosted on GitHub at gdsfactory.github.io and commercially at gdsfactory.com.