What is the use of Behaviour Driven Development (BDD) in Agile methodology?

Answer

BDD in Agile Methodology

The Connection

In Agile, requirements are expressed as User Stories ("As a user, I want to... so that..."). BDD extends this by converting user stories into executable Gherkin scenarios that serve as both specification and test.

Traditional Agile vs BDD-Agile

CODE

Traditional Agile:
  Sprint → User story written in Jira
         → Dev interprets and codes
         → QA writes test cases separately
         → Gaps found late (expensive)

BDD-Agile (with Cucumber):
  Sprint Planning → 3 Amigos session (BA + Dev + QA)
                 → Write Gherkin scenarios together
                 → Dev codes until scenarios pass
                 → QA automates the same scenarios
                 → No interpretation gap

Three Amigos — Core BDD Practice

CODE

BA  → "What does the feature need to do?"
Dev → "How will we build it?"
QA  → "How can this possibly fail?"
         ↓
   Together → Write Gherkin scenarios

Advantages in Agile Context

1. Non-technical collaboration BAs use BDD to draft requirements as Gherkin feature files and provide them to developers for implementation — eliminating the Word document → misunderstanding cycle.

▸2. User Stories as Feature Files

CODE

User Story:
  As a registered customer, I want to reset my password
  So that I can regain access to my account

Becomes Gherkin Feature:
  Scenario: Reset password via email
    Given the user is on the login page
    When the user clicks "Forgot Password"
    And enters email "user@example.com"
    Then a password reset link should be sent

3. Living Documentation in Sprints Feature files checked into Git serve as always-current documentation. Unlike Word docs, they can't become stale — if the test passes, the documentation is accurate.

▸4. Continuous Testing in CI/CD

CODE

Developer pushes code
      ↓
Jenkins runs Cucumber tests automatically
      ↓
Feature file scenarios pass/fail = instant feedback
      ↓
Broken behavior detected within minutes, not sprint-end

BDD Tools Used in Agile

Tool	Role
Cucumber	BDD framework (Java/JS)
Jira + Xray	Link Gherkin scenarios to user stories
Confluence	Publish Cucumber HTML reports
Jenkins	Trigger Cucumber on every PR merge