SDLC and QA: Where Testing Fits
The Software Development Life Cycle (SDLC) describes how software is planned, built, and delivered. QA and testing should be integrated into every phase, not only at the end. This post shows where testing fits and why early involvement matters.
SDLC phases in brief
Typical phases include: requirements, design, implementation, testing, deployment, and maintenance. In Agile, these overlap in short iterations; in Waterfall, they are more sequential. QA activities apply in both models.
QA in each phase
- Requirements: Review specs for testability; identify ambiguities and risks; start test plan and acceptance criteria.
- Design: Review design for testability; plan integration and system tests; define test data and environments.
- Implementation: Execute unit and integration tests; perform early functional testing; prepare automation.
- Testing: Execute system and UAT; regression; performance and security checks as needed.
- Deployment & maintenance: Smoke tests; production monitoring; regression on fixes and changes.
Shift-left testing
“Shift left” means starting testing earlier—in requirements and design—so defects are found when they are cheapest to fix. Test design and reviews in early phases are key QA contributions.
Summary
- QA and testing belong in every SDLC phase, not only “testing.”
- Early involvement (requirements and design) reduces cost and risk.
- Align your test plan and activities with the life cycle your team uses (Agile, Waterfall, or hybrid).