performance-profiling▌
davila7/claude-code-templates · updated Apr 8, 2026
Measure, analyze, optimize - in that order.
Performance Profiling
Measure, analyze, optimize - in that order.
🔧 Runtime Scripts
Execute these for automated profiling:
| Script | Purpose | Usage |
|---|---|---|
scripts/lighthouse_audit.py |
Lighthouse performance audit | python scripts/lighthouse_audit.py https://example.com |
1. Core Web Vitals
Targets
| Metric | Good | Poor | Measures |
|---|---|---|---|
| LCP | < 2.5s | > 4.0s | Loading |
| INP | < 200ms | > 500ms | Interactivity |
| CLS | < 0.1 | > 0.25 | Stability |
When to Measure
| Stage | Tool |
|---|---|
| Development | Local Lighthouse |
| CI/CD | Lighthouse CI |
| Production | RUM (Real User Monitoring) |
2. Profiling Workflow
The 4-Step Process
1. BASELINE → Measure current state
2. IDENTIFY → Find the bottleneck
3. FIX → Make targeted change
4. VALIDATE → Confirm improvement
Profiling Tool Selection
| Problem | Tool |
|---|---|
| Page load | Lighthouse |
| Bundle size | Bundle analyzer |
| Runtime | DevTools Performance |
| Memory | DevTools Memory |
| Network | DevTools Network |
3. Bundle Analysis
What to Look For
| Issue | Indicator |
|---|---|
| Large dependencies | Top of bundle |
| Duplicate code | Multiple chunks |
| Unused code | Low coverage |
| Missing splits | Single large chunk |
Optimization Actions
| Finding | Action |
|---|---|
| Big library | Import specific modules |
| Duplicate deps | Dedupe, update versions |
| Route in main | Code split |
| Unused exports | Tree shake |
4. Runtime Profiling
Performance Tab Analysis
| Pattern | Meaning |
|---|---|
| Long tasks (>50ms) | UI blocking |
| Many small tasks | Possible batching opportunity |
| Layout/paint | Rendering bottleneck |
| Script | JavaScript execution |
Memory Tab Analysis
| Pattern | Meaning |
|---|---|
| Growing heap | Possible leak |
| Large retained | Check references |
| Detached DOM | Not cleaned up |
5. Common Bottlenecks
By Symptom
| Symptom | Likely Cause |
|---|---|
| Slow initial load | Large JS, render blocking |
| Slow interactions | Heavy event handlers |
| Jank during scroll | Layout thrashing |
| Growing memory | Leaks, retained refs |
6. Quick Win Priorities
| Priority | Action | Impact |
|---|---|---|
| 1 | Enable compression | High |
| 2 | Lazy load images | High |
| 3 | Code split routes | High |
| 4 | Cache static assets | Medium |
| 5 | Optimize images | Medium |
7. Anti-Patterns
| ❌ Don't | ✅ Do |
|---|---|
| Guess at problems | Profile first |
| Micro-optimize | Fix biggest issue |
| Optimize early | Optimize when needed |
| Ignore real users | Use RUM data |
Remember: The fastest code is code that doesn't run. Remove before optimizing.
Discussion
Product Hunt–style comments (not star reviews)- No comments yet — start the thread.
Ratings
4.5★★★★★48 reviews- ★★★★★Chinedu Liu· Dec 28, 2024
I recommend performance-profiling for anyone iterating fast on agent tooling; clear intent and a small, reviewable surface area.
- ★★★★★Lucas Yang· Dec 8, 2024
Solid pick for teams standardizing on skills: performance-profiling is focused, and the summary matches what you get after install.
- ★★★★★Chinedu Smith· Dec 4, 2024
performance-profiling fits our agent workflows well — practical, well scoped, and easy to wire into existing repos.
- ★★★★★Rahul Santra· Nov 23, 2024
Solid pick for teams standardizing on skills: performance-profiling is focused, and the summary matches what you get after install.
- ★★★★★Chinedu Ghosh· Nov 23, 2024
We added performance-profiling from the explainx registry; install was straightforward and the SKILL.md answered most questions upfront.
- ★★★★★Emma Menon· Nov 19, 2024
Useful defaults in performance-profiling — fewer surprises than typical one-off scripts, and it plays nicely with `npx skills` flows.
- ★★★★★Aarav Patel· Nov 19, 2024
performance-profiling is among the better-maintained entries we tried; worth keeping pinned for repeat workflows.
- ★★★★★Pratham Ware· Oct 14, 2024
performance-profiling is among the better-maintained entries we tried; worth keeping pinned for repeat workflows.
- ★★★★★Lucas Zhang· Oct 14, 2024
performance-profiling reduced setup friction for our internal harness; good balance of opinion and flexibility.
- ★★★★★Aarav Rao· Oct 10, 2024
Registry listing for performance-profiling matched our evaluation — installs cleanly and behaves as described in the markdown.
showing 1-10 of 48