Test Strategy Design

Purpose

Design a comprehensive testing strategy for a project or module, selecting the appropriate mix of test types, tools, and coverage targets based on the system's risk profile, architecture, and team capabilities.

When to Use

• •Starting a new project and establishing testing practices
• •Reviewing and improving an existing test strategy
• •Adding a new module or service that needs a testing plan
• •Preparing for a production launch or compliance audit
• •After an incident that revealed testing gaps

Steps

Step 1: Understand the System

Gather context:

• •Architecture: Monolith, microservices, serverless, frontend SPA, etc.
• •Languages: Go, Python, TypeScript, etc.
• •Critical paths: What operations must never fail? (payments, auth, data integrity)
• •Risk profile: Financial, healthcare, consumer, internal tool?
• •Team size and experience: How much testing infrastructure can they maintain?
• •Existing tests: What exists? What's the current coverage? Any known gaps?

Step 2: Map Test Types to System Layers

Step 3: Define the Test Pyramid

Determine the distribution based on the architecture:

Backend-Heavy System:

Unit (60%) > Integration (25%) > E2E (10%) > Smoke (5%)
Property-based and fuzz tests supplement unit tests on critical paths.

Frontend-Heavy System:

Component (50%) > Integration (20%) > Visual (10%) > E2E (10%) > A11y (10%)

Full-Stack Application:

Unit/Component (50%) > Integration (25%) > E2E (10%) > Visual/A11y (10%) > Smoke (5%)

Step 4: Select Tools per Test Type

For each test type in the strategy, select tools based on the language and ecosystem:

Go:

Python:

TypeScript:

Step 5: Define Coverage Targets

Set realistic, risk-adjusted targets:

Step 6: Design CI Pipeline Integration

Map test types to pipeline stages:

on_every_commit:
  - lint
  - unit tests
  - component tests
  - accessibility tests (axe)

on_pull_request:
  - all of the above
  - integration tests
  - snapshot tests
  - visual regression tests
  - mutation tests (incremental, changed files only)

on_merge_to_main:
  - all of the above
  - E2E tests
  - smoke tests
  - full mutation testing

nightly:
  - fuzz testing (extended duration)
  - property-based tests (extended examples)
  - performance/load tests
  - security scanning (SAST/DAST)

Step 7: Establish Test Quality Standards

Define standards for test code itself:

• •Naming: TestFunctionName_Scenario_ExpectedBehavior (Go), it('does X when Y') (JS)
• •Structure: Arrange-Act-Assert (unit), Given-When-Then (BDD)
• •Independence: Tests must not depend on execution order
• •Speed: Unit < 100ms, integration < 5s, E2E < 30s per test
• •Determinism: No flaky tests allowed in main branch

Step 8: Plan for Maintenance

• •Flaky test quarantine: Move flaky tests to a separate suite, fix within 1 sprint
• •Test debt tracking: Track untested modules and weak test areas
• •Coverage trending: Monitor coverage trends over time (never let it decrease)
• •Regular strategy reviews: Quarterly review of test strategy effectiveness

Output Format

Produce:

1. •Test strategy document mapping test types to system layers
2. •Tool selection matrix with justifications
3. •Coverage targets per module/risk level
4. •CI pipeline configuration showing when each test type runs
5. •Test quality standards and naming conventions
6. •Maintenance plan for ongoing test health