This hardware disseminated and evolved organically, even accidentally. Generation 2 hardware adopters were motivated by the scientific results obtained using the Generation 1 tool, and the offer to translate the technology within the context of ongoing government-funded research projects. When developing the chamber, establishing the validity of the color change proxy was essential in encouraging hardware adoption on the other sites. In Free Open Source Hardware (FOSH) literature, this step can be likened to proof of concept and validation, where the utility of a design is firmly established, and its functionality proven . In our case, the MIT team devoted the upfront cost to establish the color change proxy through prior research, which formed the foundation of the aging chamber's experimental utility , . While this proxy was developed in thin-film devices, the confirmed utility encouraged other sites to implement the same experimental design in other sample types. The Stanford and Haverford sites evolved the hardware toward solar-cell devices and bulk crystal samples, respectively. This expanded catalog of known use cases makes it easier for further groups to adopt the hardware in the future, and establishes a rigorous, peer-reviewed foundation for further researchers to reference, motivating the Generation 1 and 2 tool-builders to document their work.