Quality Standards Overview

Quality is non-negotiable at YeboLearn. Our standards ensure reliable, performant, and secure software that serves students and teachers effectively.

Quality Philosophy

Quality Enables Speed

Common Misconception: Quality slows down development

Reality at YeboLearn: Quality enables sustainable high velocity

• Less time debugging production issues
• Faster feature development (solid foundation)
• Confident deployments (comprehensive testing)
• Lower technical debt (intentional design)

Balance, Not Perfection

We Don't: Aim for 100% test coverage or zero bugs We Do: Set realistic standards and meet them consistently

Target Standards:
✓ 70%+ test coverage (not 100%)
✓ 99.9% uptime (not 100%)
✓ <2% defect escape rate (not 0%)
✓ <200ms API response time p95 (not p100)

Why: Diminishing returns beyond these targets

Everyone Owns Quality

Quality is not just QA's job:

• Developers: Write tests, review code, fix bugs
• Product: Define clear acceptance criteria
• Design: Create consistent, accessible UX
• QA: Validate features, find edge cases
• DevOps: Monitor, alert, optimize

Quality Metrics

Code Quality

Test Coverage:

Current: 73%
Target: 70% minimum
Trend: ↑ (improving)

Breakdown by Module:
- Payment processing: 92% ✓
- AI features: 85% ✓
- Authentication: 78% ✓
- Student dashboard: 68% ⚠️
- Quiz engine: 71% ✓

Action: Increase dashboard coverage to 70%+

Code Review:

Metrics (Last 30 Days):
- Average review time: 3.2 hours
- PRs requiring changes: 78%
- PRs approved first time: 22%
- Comments per PR: 5.8 average

Targets:
- Review time: <4 hours ✓
- PRs requiring changes: 70-80% ✓
- Comments per PR: 4-8 (healthy discussion) ✓

Technical Debt:

Total Debt: 42 story points
High Priority: 21 points
Medium Priority: 21 points

Debt Ratio: 12% (debt vs total codebase)
Target: <15%
Status: ✓ Healthy

Debt Paydown:
- Sprint capacity for debt: 20%
- Debt added per sprint: 4 points avg
- Debt paid per sprint: 7 points avg
- Net reduction: -3 points/sprint ✓

Static Analysis:

ESLint Issues:
- Errors: 0 ✓ (blocking)
- Warnings: 12 (non-blocking)

TypeScript Errors: 0 ✓

Complexity Issues:
- High complexity functions: 3
- Action: Refactor in Sprint 27

Performance Benchmarks

API Response Time:

Current Metrics:
- p50: 145ms (target: <200ms) ✓
- p95: 380ms (target: <500ms) ✓
- p99: 820ms (target: <1s) ✓

Endpoints by Performance:
Fast (<100ms p50):
✓ Health check: 12ms
✓ Authentication: 45ms
✓ Course list: 78ms

Medium (100-200ms p50):
✓ Student dashboard: 145ms
✓ Quiz list: 132ms

Slow (>200ms p50):
⚠️ Student progress: 210ms (needs optimization)
⚠️ Analytics: 280ms (acceptable for admin)

Page Load Time:

Current Metrics:
- Dashboard: 1.9s (target: <2s) ✓
- Quiz page: 1.2s (target: <2s) ✓
- Course page: 1.6s (target: <2s) ✓

Core Web Vitals:
- LCP: 2.1s (target: <2.5s) ✓
- FID: 45ms (target: <100ms) ✓
- CLS: 0.05 (target: <0.1) ✓

Lighthouse Scores (Mobile):
- Performance: 87 ⚠️ (target: >90)
- Accessibility: 95 ✓
- Best Practices: 92 ✓
- SEO: 100 ✓

Database Performance:

Query Performance:
- Average: 35ms (target: <50ms) ✓
- p95: 180ms (target: <200ms) ✓
- p99: 280ms (target: <500ms) ✓

Index Hit Rate: 98.5% (target: >95%) ✓
Cache Hit Rate: 94% (target: >90%) ✓

Slow Queries (>100ms):
- Student progress aggregation: 145ms
- Course enrollment stats: 120ms
- Action: Optimization in Sprint 26-27

AI Feature Performance:

Essay Grading:
- Average: 45s (target: <30s) ⚠️
- p95: 68s (target: <45s) ⚠️
- Success rate: 98.5% ✓

Quiz Generation:
- Average: 8s (target: <10s) ✓
- p95: 12s (target: <15s) ✓
- Success rate: 99.2% ✓

Action: AI performance optimization in Sprint 27

Security Standards

Authentication & Authorization:

✓ JWT tokens with 1-hour expiry
✓ Refresh tokens with 30-day expiry
✓ Password hashing (bcrypt, cost 12)
✓ Rate limiting on auth endpoints (5 attempts/min)
✓ HTTPS only (TLS 1.2+)
✓ CORS properly configured
✓ SQL injection prevention (parameterized queries)
✓ XSS prevention (input sanitization)

Data Protection:

✓ PII encrypted at rest (database encryption)
✓ Sensitive data in Secret Manager (not env files)
✓ Database backups encrypted
✓ GDPR compliance (data export, deletion)
✓ Audit logs for sensitive operations
✓ No secrets in code or logs

Security Scanning:

Automated Scans:
✓ Dependency scanning (npm audit)
✓ Container scanning (Google Container Analysis)
✓ Static code analysis (CodeQL)
✓ License compliance

Frequency:
- On every PR (blocking)
- Daily on main branch
- Weekly comprehensive scan

Current Status:
- Critical vulnerabilities: 0 ✓
- High vulnerabilities: 0 ✓
- Medium vulnerabilities: 2 (tracked, non-blocking)

Compliance:

✓ GDPR (data privacy)
✓ POPIA (South African data protection)
✓ PCI-DSS (via Stripe/M-Pesa, not direct)
✓ FERPA considerations (education records)

Regular Reviews:
- Security audit: Quarterly
- Privacy policy review: Bi-annually
- Compliance check: Monthly

Reliability Metrics

Uptime:

Current (30 days): 99.97%
Target: 99.9% ✓
Exceeded by: 0.07%

Historical:
- Last month: 99.96%
- 3-month avg: 99.95%
- 12-month avg: 99.93%

Downtime Analysis:
- Planned maintenance: 5 min
- Unplanned incidents: 8 min
- Total: 13 min (43 min budget)

Error Rates:

API Errors:
- Current: 0.3% (target: <1%) ✓
- Breakdown:
  - 4xx (client): 0.2%
  - 5xx (server): 0.1%

Frontend Errors:
- Current: 0.1% (target: <0.5%) ✓
- Most common: Network timeouts

Incident Response:

Mean Time to Detect (MTTD): 2 min (target: <5 min) ✓
Mean Time to Resolve (MTTR): 25 min (target: <1 hour) ✓

Incident Breakdown (Last Quarter):
- P0 (Critical): 0
- P1 (High): 2 (avg resolution: 35 min)
- P2 (Medium): 8 (avg resolution: 2 hours)
- P3 (Low): 15 (avg resolution: 1 day)

Quality Gates

Pre-Commit Quality Gates

Before Code Reaches Repository:

Developer Local Checks:
- [ ] Code compiles (TypeScript)
- [ ] Linter passes (ESLint)
- [ ] Formatter applied (Prettier)
- [ ] Unit tests pass
- [ ] No console.log or debug code

Git Hooks (Automated):

# Pre-commit hook
npm run lint
npm run type-check
npm run test:quick # Fast unit tests only

# Pre-push hook
npm run test # Full test suite

Pre-Merge Quality Gates

GitHub Actions CI Pipeline:

✓ Install dependencies
✓ Run linting (ESLint, Prettier)
✓ Type checking (TypeScript)
✓ Run unit tests
✓ Run integration tests
✓ Build application
✓ Check bundle size (<500kb limit)
✓ Security scan (npm audit)
✓ Code coverage report (must maintain 70%+)

Status: Must be green to merge

Code Review Requirements:

Required:
- [ ] At least 1 approving review
- [ ] All CI checks passing
- [ ] No unresolved comments
- [ ] No merge conflicts

Reviewer Checklist:
- [ ] Code is readable and maintainable
- [ ] Tests cover new functionality
- [ ] No obvious bugs or security issues
- [ ] Follows coding standards
- [ ] Documentation updated if needed

Pre-Production Quality Gates

Staging Validation:

Before Deploy to Production:
- [ ] All features tested in staging
- [ ] QA sign-off
- [ ] Stakeholder approval (demos)
- [ ] Performance benchmarks met
- [ ] Security scan passed
- [ ] Database migrations tested
- [ ] Rollback plan documented
- [ ] Monitoring alerts configured

Release Checklist:

- [ ] Changelog generated
- [ ] Version number updated
- [ ] Release notes written
- [ ] Deployment runbook ready
- [ ] On-call engineer assigned
- [ ] Team notified of deployment
- [ ] Post-deployment tests prepared

Quality Monitoring

Continuous Monitoring

Application Monitoring:

Metrics Tracked:
✓ Request rate (requests/second)
✓ Response time (p50, p95, p99)
✓ Error rate (%)
✓ Active users (concurrent)
✓ Database performance
✓ Cache hit rates
✓ AI API latency

Frequency: Real-time (1-minute resolution)
Retention: 90 days

User Experience Monitoring:

Real User Monitoring (RUM):
✓ Page load times
✓ Time to interactive
✓ First contentful paint
✓ Largest contentful paint
✓ Cumulative layout shift
✓ JavaScript errors
✓ Network errors

Tool: Custom implementation + Google Analytics
Sample: 100% of users

Business Metrics:

✓ Quiz completions per hour
✓ AI feature usage
✓ Payment success rate
✓ Course enrollments
✓ User signups
✓ Daily/monthly active users

Dashboard: Grafana
Alerts: Slack + PagerDuty

Quality Dashboards

Engineering Dashboard:

Deployment Metrics:
- Deployment frequency: 12/week to dev, 1/2 weeks to prod
- Lead time: 2-5 days from commit to production
- Change failure rate: 3% (target: <5%)
- MTTR: 25 minutes

Code Quality:
- Test coverage: 73%
- Code review time: 3.2 hours
- Technical debt: 42 story points
- ESLint warnings: 12

Performance:
- API p95 response time: 380ms
- Page load time: 1.9s average
- Database query time: 35ms average

Product Health Dashboard:

User Metrics:
- Daily active users: 2,340
- Monthly active users: 8,900
- User retention (D7): 65%
- User retention (D30): 42%

Engagement:
- Quizzes per user: 4.2/week
- AI features usage: 38% of users
- Payment conversion: 12%

Quality:
- Bug reports: 8/week
- Support tickets: 15/week
- User satisfaction: 8.4/10

Quality Improvement Process

Weekly Quality Review

Every Monday (30 min):

Review:
- Test coverage changes
- Slow tests (>30s) and optimize
- Failed tests in CI
- Production errors (last week)
- Performance regressions

Actions:
- Create issues for quality gaps
- Assign owners to quality improvements
- Update quality targets if needed

Monthly Quality Retrospective

First Friday of Month (1 hour):

Analyze:
- Quality metrics trends
- Production incidents root causes
- Technical debt growth
- Team feedback on quality

Outcomes:
- Quality improvement initiatives
- Process adjustments
- Tool improvements
- Training needs identified

Quarterly Quality Audit

End of Each Quarter:

Comprehensive Review:
- Security audit (external if budget allows)
- Performance benchmarking
- Code quality deep dive
- Infrastructure review
- Compliance check

Deliverables:
- Quality audit report
- Improvement roadmap
- Investment priorities

Quality Culture

Quality Best Practices

Do:

• ✓ Write tests as you code
• ✓ Review code thoroughly
• ✓ Monitor production proactively
• ✓ Fix root causes, not symptoms
• ✓ Automate quality checks
• ✓ Share quality ownership

Don't:

• ✗ Skip tests to "move faster"
• ✗ Approve PRs without review
• ✗ Ignore quality metrics
• ✗ Band-aid production issues
• ✗ Manual quality checks (automate!)
• ✗ Blame individuals for bugs

Quality Champions

Rotating Role (Weekly):

Responsibilities:
- Monitor quality metrics daily
- Triage failing tests
- Coordinate quality improvements
- Share quality wins in standup
- Escalate quality concerns

Benefits:
- Shared ownership
- Knowledge distribution
- Fresh perspectives

Quality Celebrations

Celebrate Quality Wins:

• 🎉 Zero production bugs for 2 weeks
• 🚀 Deployment with no rollback
• 📈 Test coverage milestone (70%, 75%, 80%)
• ⚡ Performance improvement (>20%)
• 🏆 Clean security audit

Recognition:

• Shoutout in team meeting
• Slack announcement
• Contribution to quality metrics dashboard

Related Documentation

• Code Standards - Detailed coding standards
• Monitoring Guide - Monitoring and alerting setup
• Testing Strategy - Testing approach
• Development Workflow - Day-to-day process