Agent skill
performance-profiling
Identify performance bottlenecks systematically. Measure before optimizing.
Install this agent skill to your Project
npx add-skill https://github.com/timequity/plugins/tree/main/craft-coder/performance-profiling
SKILL.md
Performance Profiling
Core Principle
Measure first. Optimize second. Verify third.
Never optimize based on intuition. Profile to find actual bottlenecks.
The Process
1. Establish Baseline
# Node.js
node --prof app.js
node --prof-process isolate-*.log > profile.txt
# Browser
Performance tab → Record → Analyze
2. Identify Bottlenecks
Look for:
- Functions with high "self time"
- Unexpected call counts
- Memory allocations in hot paths
- N+1 queries
3. Form Hypothesis
"Function X is slow because Y"
4. Optimize Minimally
One change at a time:
- Caching
- Algorithm improvement
- Batch operations
- Lazy loading
5. Verify Improvement
Compare against baseline. Must be measurably better.
Common Bottlenecks
| Symptom | Likely Cause |
|---|---|
| Slow page load | Large bundle, blocking resources |
| Slow API | N+1 queries, missing indexes |
| Memory growth | Leaks, unbounded caches |
| CPU spikes | Inefficient loops, regex |
Tools
Node.js:
--profflagclinic.js0xflame graphs
Browser:
- DevTools Performance
- Lighthouse
- WebPageTest
Database:
- EXPLAIN ANALYZE
- Query logs
- Connection pool stats
Red Flags
- Optimizing without profiling
- "I think this is slow"
- Premature optimization
- Micro-optimizations in cold paths
Recommended Agent Skills
Expand your agent's capabilities with these related and highly-rated skills.
timequity/plugins
claude-code-course
Learn Claude Code in 5 hands-on lessons. From basics to building applications. Use when: user wants to learn Claude Code, asks "how do I...", or is new. Triggers: "learn", "teach me", "how does this work", "I'm new", "course".
timequity/plugins
foundations
Claude Code basics for new users. Covers essential concepts and commands. Use when: user is new to Claude Code or routed here by learning-path assessment.
timequity/plugins
advanced
Claude Code mastery for power users. Build agents, MCP servers, publish plugins. Use when: user wants to create agents, build integrations, or publish plugins.
timequity/plugins
lessons
Lesson content for Claude Code Course. Use when: loading lesson content. Internal skill - contains lesson files.
timequity/plugins
intermediate
Claude Code customization for comfortable users. Covers skills, commands, MCP, hooks. Use when: user knows basics and wants to customize Claude Code.
timequity/plugins
course-help
Help and navigation for Claude Code Course. Use when: user asks about the course, lessons, or progress. Triggers: "help", "course help", "what lessons", "my progress".
Didn't find tool you were looking for?