Testing regression strategy

Testing Regression Strategy

Overview

Use this skill to select regression coverage that maximizes risk reduction within execution constraints.

Scope Boundaries

• Use when not all tests can run every change and selection policy is required.
• Typical requests:
  • Optimize regression coverage under CI time budget.
  • Define mandatory versus conditional suites by risk.
  • Map change impact to regression gates.
• Do not use when:
  • The task is implementing one specific test case only.
  • The task is observability/alert policy design (observability-*).

Inputs

• Release risk profile and CI budget
• Test inventory with cost, flakiness, and detection value
• Change-impact and component criticality model

Outputs

• Tiered regression policy (always-run, conditional, periodic)
• Decision record for suite selection logic and trade-offs
• Verification checklist and gap register

Workflow

1. Classify system areas by business and technical risk.
2. Quantify each suite by execution cost and detection value in assets/regression-tiering-template.csv.
3. Compare selection policies and choose one with rationale.
4. Define trigger rules for conditional suites.
5. Publish policy, residual risk, and review cadence.

Quality Gates

• High-risk areas are always covered by mandatory gates.
• Selection policy is explainable and auditable.
• Budget trade-offs are explicit, not implicit.
• Policy includes periodic recalibration triggers.

Failure Handling

• Stop when high-risk areas are uncovered by mandatory tests.
• Escalate when budget and required risk coverage conflict.

Bundled Resources

• references/trigger-and-examples.md: trigger patterns, anti-patterns, and deliverable expectations.
• assets/regression-tiering-template.csv: quick-start matrix for always/conditional/nightly suite selection.