Introducing Behavior-Driven Development

BDD emphasizes testing a system’s overall behavior rather than verifying individual functions. Rather than focusing solely on isolated code units, BDD aims to ensure that the software aligns with business requirements and meets user expectations.

BDD builds on TDD while incorporating a business perspective, making it particularly compatible with domain-driven design (DDD). This approach utilizes a narrative style for tests, written in a manner easily understandable by everyone—developers, testers, and business stakeholders alike. The goal is to establish a ubiquitous language. This shared vocabulary reflects the core concepts of the domain, making the tests clear and relevant to both technical and non-technical team members.

A common way to structure these behavior-focused tests is through the given-when-then (GWT) format. Let’s look at this format:

• Given: Set up the initial context
• When: Describe the action...