ops-performance

name	ops-performance
description	Performance analysis for Expo + serverless backend projects. Runs Lighthouse audits, bundle size analysis, and k6 load tests.
allowed-tools	["Bash","Read"]

Ops: Performance

Analyze application performance.

Argument: $ARGUMENTS — analysis type (lighthouse, bundle, k6, all; default: all) and optional target environment

Path Convention

• Frontend: Current project directory (.)
• Backend: ${BACKEND_DIR:-../backend-v2} — set BACKEND_DIR in .claude/settings.local.json if your backend is elsewhere

Discovery

1. Read frontend package.json for lighthouse:check, export:web, analyze:bundle scripts
2. Read backend package.json for k6:* scripts
3. Read e2e/constants.ts or .env.* files for environment URLs

Lighthouse Audit

Against Local

npx lighthouse http://localhost:8081 \
  --output=json \
  --output-path=./lighthouse-local.json \
  --chrome-flags='--headless --no-sandbox'

Against Deployed Environment

Discover frontend URLs from e2e/constants.ts or .env.* files:

npx lighthouse https://{env_url} \
  --output=json \
  --output-path=./lighthouse-{env}.json \
  --chrome-flags='--headless --no-sandbox'

LHCI (Lighthouse CI — uses project config)

bun run lighthouse:check

Parse Lighthouse Results

cat lighthouse-{env}.json | jq '{
  performance: .categories.performance.score,
  accessibility: .categories.accessibility.score,
  bestPractices: .categories["best-practices"].score,
  seo: .categories.seo.score,
  fcp: .audits["first-contentful-paint"].displayValue,
  lcp: .audits["largest-contentful-paint"].displayValue,
  tbt: .audits["total-blocking-time"].displayValue,
  cls: .audits["cumulative-layout-shift"].displayValue,
  si: .audits["speed-index"].displayValue
}'

Bundle Analysis

Full Analysis (export + source-map-explorer)

bun run export:web && bun run analyze:bundle

Quick Size Check

bun run export:web
echo "=== Total Bundle Size ==="
du -sh dist/
echo ""
echo "=== Largest JS Files ==="
find dist -name "*.js" -exec ls -lhS {} + 2>/dev/null | head -20

k6 Load Tests

Discover available k6 scripts from the backend package.json (matching k6:*).

Smoke Test (minimal load, verify endpoints work)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:smoke

Load Test (normal traffic simulation)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:load

Stress Test (push beyond normal capacity)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:stress

Spike Test (sudden traffic burst)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:spike

Docker-based k6 (no local k6 install needed)

cd "${BACKEND_DIR:-../backend-v2}"
bun run k6:docker:smoke
bun run k6:docker:load

Output Format

Lighthouse Scores

Metric	Score	Rating
Performance	0.85	GOOD
Accessibility	0.92	GOOD
Best Practices	0.88	GOOD
SEO	0.95	GOOD

Core Web Vitals

Metric	Value	Threshold	Status
FCP (First Contentful Paint)	1.2s	< 1.8s	PASS
LCP (Largest Contentful Paint)	2.1s	< 2.5s	PASS
TBT (Total Blocking Time)	150ms	< 200ms	PASS
CLS (Cumulative Layout Shift)	0.05	< 0.1	PASS

Bundle Size

Category	Size	Notes
Total dist/	4.2 MB
Largest chunk	1.1 MB	vendor.js

k6 Results

Metric	Value
Requests/sec	450
Avg response time	120ms
p95 response time	350ms
Error rate	0.1%

Include recommendations for any metrics that fall below thresholds.