A feature can pass its tests and still fail its users. Requirements handed from stakeholder to analyst to developer to tester create opportunities for assumptions to go unnoticed. Behavior-driven development (BDD) replaces that relay with conversations among business stakeholders, analysts, developers, and testers. Together they identify the business goal, discuss concrete examples of expected behavior, and agree on what would show that a feature works. section 1.1 section 1.5
Repeat the following activities for each feature, rather than treating requirements as a one-time handoff:
- Find the business goal behind a request. Ask what users need to achieve instead of accepting a proposed solution or trying to fix every requirement up front. section 2.3.1 section 4.2.8
- Bring users, analysts, developers, and testers into the conversation. Explore examples and counterexamples to expose ambiguity, technical constraints, and questions about testability. section 2.3.2 section 1.5
- Turn agreed examples into acceptance criteria. A scenario can state a context, an action, and an expected outcome using Given, When, and Then. section 3.4
- Where useful, automate those scenarios as business-readable executable specifications. Work from the acceptance criteria toward the code, using low-level specifications or unit tests to describe component behavior. section 2.3.7 section 2.6
- Run the automated checks for feedback and use their results as living documentation of delivered behavior. Return to conversation when examples reveal a mistaken assumption or a changing need. section 2.3 section 2.4.3
An example changes the requirement
Suppose a commuter asks for the next train from Hornsby to Chatswood. An initial scenario says only that the next train leaves at 8:02. Reading it together reveals a missing condition: more than one line departs from Hornsby, so the scenario must identify the line going to Chatswood. Further examples distinguish returning one departure from showing several suitable departures. The conversation makes the acceptance criterion more precise before implementation. section 3.4
BDD is a collection of practices, not a replacement for Scrum or Kanban and not merely a test-writing syntax. It extends ideas from test-driven development to business-facing requirements discovery while also applying behavior-focused thinking to unit tests. Its benefits depend on timely stakeholder participation: automated checks cannot recover business intent that the team never discussed. section 1.3 section 2.5.1 section 2.6
