Behaviour Driven Development (BDD) is a software development approach that emphasizes collaboration between stakeholders such as developers, quality assurance professionals, and non-technical or business participants in a software project. A BDD developer's role is multifaceted, involving a variety of tasks and responsibilities. . Collaboration: BDD developers work closely with all stakeholders to understand the behavior of the software from the user's perspective. This involves regular meetings and discussions to clarify the expected behavior of the software. . Writing User Stories: BDD developers write user stories that describe how the software should behave from the user’s perspective. These stories use a specific syntax, often "Given-When-Then", to describe the context, action, and expected result. . Defining Acceptance Criteria: Along with the user stories, BDD developers define acceptance criteria which specify the conditions that the software must meet to be considered complete. This helps ensure that all stakeholders have a shared understanding of what constitutes a finished feature. . Writing and Implementing Tests: BDD developers write automated tests based on the user stories and acceptance criteria. These tests are written in a human-readable language that describes the software's behavior. The developers then write the code to make these tests pass, ensuring that the software behaves as expected. . Refactoring: BDD developers continuously refactor their code to keep it clean and maintainable. This makes it easier to add new features and fix bugs in the future. . Documentation: Since the tests in BDD are written in a language that's easy to understand, they serve as a form of documentation. This makes it easier for new team members to understand how the software works. . Continuous Integration: BDD developers often use Continuous Integration tools to automatically run their tests whenever changes are made to the code. This helps catch bugs and regressions early. . Iterative Development: BDD developers work in small, incremental steps, constantly communicating with stakeholders and refining the software's behavior based on feedback. In summary, a BDD developer's role involves a lot of collaboration, communication, and clear documentation, all aimed at ensuring that the software meets the needs and expectations of its users.