---|-----|-----|-----|--------| | /dashboard | 1.8s | 0.03 | 95ms | PASS |

Handoff to Next Gate

• Ready for Gate 7 (Code Review): YES

Dev Frontend Performance Testing (Gate 6)

Overview

Ensure all frontend pages meet Core Web Vitals thresholds, achieve Lighthouse Performance > 90, maintain bundle size within budget, and minimize client component usage.

Core principle: Performance is a feature. Users on slow devices and connections deserve a fast experience. Performance budgets are enforced, not suggested.

<block_condition>

• LCP > 2.5s on any page = FAIL

• CLS > 0.1 on any page = FAIL

• INP > 200ms on any page = FAIL

• Lighthouse Performance < 90 = FAIL

• Bundle size increase > 10% without justification = FAIL </block_condition>

CRITICAL: Role Clarification

This skill ORCHESTRATES. Frontend QA Analyst Agent (performance mode) EXECUTES.

Who Responsibility

This Skill Gather requirements, dispatch agent, track iterations

QA Analyst Frontend Agent Run Lighthouse, measure CWV, analyze bundles, audit components

Standards Reference

MANDATORY: Load testing-performance.md standards via WebFetch.

<fetch_required> https://raw.githubusercontent.com/LerianStudio/ring/main/dev-team/docs/standards/frontend/testing-performance.md </fetch_required>

Step 1: Validate Input

REQUIRED INPUT:

• unit_id: [task/subtask being tested]
• implementation_files: [files from Gate 0]

OPTIONAL INPUT:

• performance_baseline: [previous metrics for comparison]
• gate5_handoff: [full Gate 5 output]

if any REQUIRED input is missing: → STOP and report: "Missing required input: [field]"

Step 2: Dispatch Frontend QA Analyst Agent (Performance Mode)

Task tool: subagent_type: "ring:qa-analyst-frontend" prompt: | MODE: PERFORMANCE TESTING (Gate 6)

**Standards:** Load testing-performance.md

**Input:**
- Unit ID: {unit_id}
- Implementation Files: {implementation_files}
- Baseline: {performance_baseline or "N/A"}

**Requirements:**
1. Measure Core Web Vitals (LCP, CLS, INP) on all affected pages
2. Run Lighthouse audit (Performance score > 90)
3. Analyze bundle size change vs baseline
4. Audit 'use client' usage (should be < 40% of components)
5. Detect performance anti-patterns (bare <img>, useEffect for fetching, etc.)
6. Verify sindarian-ui imports are tree-shakeable

**Output Sections Required:**
- ## Performance Testing Summary
- ## Core Web Vitals Report
- ## Handoff to Next Gate

Step 3: Evaluate Results

Parse agent output:

if "Status: PASS" in output: → Gate 6 PASSED → Return success with metrics

if "Status: FAIL" in output: → Dispatch fix to implementation agent (ring:frontend-engineer) → Re-run performance tests (max 3 iterations) → If still failing: ESCALATE to user

Step 4: Generate Output

Performance Testing Summary

Status: {PASS|FAIL} LCP: {value}s (< 2.5s) CLS: {value} (< 0.1) INP: {value}ms (< 200ms) Lighthouse: {score} (> 90) Bundle Change: {+X%} (< 10%)

Core Web Vitals Report

Bundle Analysis

Server Component Audit

Anti-Pattern Detection

Handoff to Next Gate

• Ready for Gate 7 (Code Review): {YES|NO}
• Iterations: {count}

Severity Calibration

Severity Criteria Examples

CRITICAL Core Web Vitals fail, page unusable LCP > 4s, CLS > 0.25, INP > 500ms

HIGH Threshold violations, major regressions Lighthouse < 90, bundle +20%, LCP > 2.5s

MEDIUM Minor threshold concerns, optimization opportunities Client ratio > 40%, bare img tags

LOW Best practices, minor optimizations Code splitting suggestions, cache improvements

Report all severities. CRITICAL = immediate fix (UX broken). HIGH = fix before gate pass. MEDIUM = fix in iteration. LOW = document.

Anti-Rationalization Table

See shared-patterns/shared-anti-rationalization.md for universal anti-rationalizations. Gate-specific:

Rationalization Why It's WRONG Required Action

"Works fine on my machine" Your machine ≠ user's device. Measure objectively. Run Lighthouse

"We'll optimize later" Performance debt compounds. Fix during development. Meet thresholds now

"Bundle size doesn't matter" Mobile 3G users exist. Every KB matters. Stay within budget

"Everything needs use client" Server components reduce JS. Audit first. Minimize client components

"next/image is too complex" next/image gives free optimization. Always use it. Use next/image

"Lighthouse 85 is close enough" 90 is the threshold. 85 = FAIL. Optimize to 90+