How do you identify bounded contexts in a legacy codebase?
Bounded contexts are one of the core concepts of domain-driven design (DDD), a software development approach that focuses on aligning the code with the business domain and its subdomains. A bounded context is a logical boundary that defines a consistent and coherent model of a subdomain, with its own language, rules, and behaviors. Bounded contexts help to avoid ambiguity, complexity, and coupling in large and heterogeneous systems.
However, identifying bounded contexts in a legacy codebase can be challenging, especially if the codebase is monolithic, poorly structured, or has evolved over time without a clear vision. In this article, you will learn some practical techniques to discover and define bounded contexts in a legacy codebase, and how to use them to refactor and improve your code quality and maintainability.
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Mapping functional areas:Engaging with stakeholders to map out operations within the legacy system reveals natural divisions in the model, which are indicative of bounded contexts. This collaborative approach aligns technical boundaries with business needs.
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Question-driven validation:Asking targeted questions about team dynamics, database usage, and language commonality helps clarify if separate bounded contexts exist. It's a straightforward way to demarcate logical boundaries within complex systems.