Designdokument

Designdokument, or design document, is a formal artifact used to describe the intended design of a system, product, or component. It communicates the overall architecture, the major components, their interfaces, data models, and the rationale behind design choices to developers, testers, project stakeholders, and future maintainers. The purpose is to provide a common reference that guides implementation, enables validation against requirements, and supports maintenance and evolution of the system.

A designdokument typically covers the scope and goals of the project, the stakeholders, constraints and assumptions, and a high-level architectural view. It details the design of individual components or subsystems, their responsibilities, interfaces and interaction patterns, and any data design such as models and schemas. It describes external interfaces, such as APIs or protocols, and may include user interface concepts if applicable. Non-functional requirements—performance, security, reliability, scalability, and maintainability—are documented, along with design rationales, trade-offs, and alternatives considered. The document also specifies risks, dependencies, validation criteria, test plans, and an implementation and migration plan, as well as a plan for ongoing maintenance and documentation. It may include diagrams (architecture diagrams, sequence flows), data models, and mapping to requirements for traceability.

In practice, a designdokument is created during the design phase after requirements specification and is often reviewed and updated as decisions firm up. In some organizations it is split into multiple documents or replaced by lighter design notes or architecture decision records, depending on project size and methodology.