If developers are decompiling the code of a legacy system with no documentation, this is an example of which technique?

The action of decompiling the code of a legacy system that lacks documentation falls under the category of reverse-engineering. This technique involves analyzing a system to produce a representation of the system's components or behavior, often to recover lost or not well-documented knowledge. In the context of requirements engineering, reverse-engineering allows developers to understand existing functionalities, identify gaps, and collect vital information that can inform future development or modifications to the system.

Reverse-engineering is particularly useful when no formal documentation exists, as it enables teams to deduce the purpose, operation, and logic behind different parts of the software. This knowledge can then be applied to improve the system, ensure continued usability, or support the integration of new features. It’s a common strategy in environments where the original design documents may be outdated, lost, or completely absent, which frequently occurs with legacy systems.