Large feature = significant complexity, multiple components, many edge cases.
Phase 1: Discovery participation.
- Attend Discovery sessions.
- Understand requirements.
- Identify test scenarios early.
- Estimate testing effort.
Phase 2: Test planning.
- Test plan document.
- Test cases (functional, non-functional).
- Test data needs.
- Resource plan.
Phase 3: Test development.
- Apex unit tests written alongside code (ideally TDD).
- LWC Jest tests.
- Integration tests.
- UI test automation.
Phase 4: Component testing.
- Each component tested in isolation.
- Bugs surfaced and fixed.
Phase 5: Integration testing.
- Components together.
- Cross-component flows.
- End-to-end scenarios.
Phase 6: System testing.
- Full feature in system context.
- Performance under expected load.
- Security validated.
Phase 7: UAT.
- Business users test.
- Sign-off criteria.
Phase 8: Regression.
- Automated regression on existing functionality.
- Confirm no breakage.
Phase 9: Release readiness.
- All gates met.
- Sign-off.
Phase 10: Post-release.
- Monitor production.
- Gather feedback.
- Address surfaced issues.
Common pitfalls:
- Testing too late — defects pile up.
- Insufficient regression — old features break.
- No UAT — features don't fit users.
- Inadequate edge case coverage.
Senior insight: large features need structured testing. Without phases, chaos.
The senior framing: good testing prevents production incidents. Investment justified.