Summary
Jacobson (who invented use cases in 1986) and Cockburn (who refined them with goal levels and the fully-dressed template) revisit their methodology thirty-seven years later. They argue that use cases remain essential because they force you to think about actors (who uses the system), goals (what they’re trying to accomplish), scenarios (how it works step by step), and extensions (what can go wrong at each step). The paper updates the approach for modern development while preserving the core discipline.
What it means for our work
This paper is the direct foundation for the Use Cases plugin. The methodology it describes — actors, goals, scenarios, extensions — is exactly what the plugin guides you through. The key insight we build on: use cases are a specification format, not a code generation format. The output is a document that captures what the system should do, which then feeds into Z Spec for formal modeling or directly into implementation. Requirements first, code second.