Performance Profiler: Find the Bottleneck Before Your Users Do

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TL;DR: Profile your Node.js application, identify bottlenecks, detect memory leaks, and measure event loop lag with flamegraph output.

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The 10-Second Pitch

• What it is: A runtime profiler that attaches to your Node.js process and generates actionable performance reports.
• Who it's for: Backend engineers, SREs, performance-obsessed architects.
• Why it matters: Profiling in production is hard. This gives you production-grade insights without the overhead.
• Stack: Node.js (built-in inspector protocol), outputs JSON + SVG flamegraphs.

Setup Directions

Prerequisites

• Node.js >= 18
• A running Node.js service to profile

Step 1 - Install

bash npm install @mrtech/performance-profiler --save-dev

Step 2 - Profile

bash npx perf-profiler attach --pid=$(pgrep -f "node.*server.js") --duration=60s

Step 3 - Read Report

bash npx perf-profiler report --input=./reports/profile-123456.json --format=html

Pros / Cons

Verdict

Performance Profiler is what you reach for when your p99 latency is degraded and your existing APM isn't giving you a clear root cause. The event loop lag measurement is the killer feature.

Skill: performance-profiler | Ecosystem: claude-code | Runtime: node | Auth: api-key