The Crystal methodologies are a lightweight and versatile software development family of methods. Team size and project priority are the principal characterizations of crystal methods. The methods were developed initially by Cockburn and are considered a lightweight development approach that promotes flexibility. The crystal family of methods focuses on teamwork, flexibility, communication, and simplicity to improve processes.
The Crystal family is identified by color to indicate the type of development. The colors include clear, yellow, orange, and red, indicating factors such as team size, system criticality, and project priorities. Color represents the weight or size of the project; the darker the color, the larger the project. Crystal orange denotes a project with around 40 developers, whereas crystal clear is more suitable for smaller projects with fewer developers. Additionally, crystal orange is more appropriate when a high degree of rigor is necessary, whereas clear is more flexible and lightweight. The color indicator of the method identifies the characteristics of the project and team and counters the one-size-fits-all ideals of other software development approaches.
The Crystal Method family provides projects with a framework for development size and criticality. Crystal is one of the more adaptable methodologies), recognizing that each project may require individual policies and processes to meet the uniqueness of the project. The principles of Crystal are passive knowledge transfer, continuous delivery, frequent releases, and automated testing. The crystal family of methods arose from the need for a customizable approach to accommodate differences in projects.