How do I install the Electron Profile skill?

Run npx skillmds@latest add keybase/electron-profile in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Electron Profile safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Electron Profile?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Electron Profile free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Electron Profile?

keybase (@keybase) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Electron Profile by keybase — Agent Skill

Name: Electron Profile
Author: keybase

File contents

DevTools Performance Trace Analysis

Parse DevTools Performance panel exports with Python scripts in scripts/ — no DevTools UI needed. A trace is one big JSON of traceEvents; a 400MB export loads in ~30s. The embedded sampling profile lives in Profile/ProfileChunk events.

Workflow

Overview — processes, busiest renderer main thread, long tasks (with time offsets), X-event category totals:
```
python3 scripts/trace-overview.py <trace.json> [--long-ms 50] [--top 30]
```
Sample attribution — self time, inclusive time, and nearest-app-frame attribution from the CPU sampling profile. Use --window (seconds, relative to first sample) to zoom into a long task found in step 1:
```
python3 scripts/trace-samples.py <trace.json> [--window FROM_S TO_S] [--top 30]
```

Both auto-pick the busiest CrRendererMain; override with --pid/--tid. Both need scripts/tracelib.py alongside.

Interpreting results (dev builds especially)

Dev-build traces are ~85-90% React dev instrumentation, NOT app code. Absolute numbers are meaningless; prod is ~10x faster. For real numbers profile the prod bundle (see prod-bundles skill), or at minimum disable the React DevTools extension while recording.

Signal	Meaning
Huge `run (:-1)` self time, `createTask`, `measure`	React 19 dev component-performance tracks: `console.createTask().run()` inside `runWithFiberInDEV`/`logComponentRender`. Not app code.
`v8::Debugger::AsyncTaskRun` dominating X-event totals	Debugger async-stack tracking (DevTools open). Dev artifact.
Effects firing twice back-to-back	StrictMode double-invoke. Dev only.
90%+ samples with no app frame on stack	Expected in dev — instrumentation + framework internals. Judge the app-frame report's relative ranking, not totals.
`performSyncWorkOnRoot` ≫ scheduler time in inclusive report	Most renders are sync (flushSync / discrete events), not concurrent. Structural signal — valid even in dev.
`pptr:internal` frames	CDP automation harness driving the app, not app code (excluded from app-frame report).
Layout / Paint / GC / EventDispatch totals in overview	Real browser work — valid signal even in dev. Compare against script time.

Judge structure, not magnitude in dev traces: sync-vs-concurrent split, Layout/Paint/GC share, which app components rank highest, burst patterns around long tasks.

Gotchas

X-event name totals are nested-inclusive (parent contains child) — relative shape only, don't sum.
Sample span < trace span is normal: sampling only covers the profiled window.
App-frame attribution skips frames whose URL contains node_modules — with Vite dev this automatically excludes React (node_modules/.vite/deps/...).
--window is relative to the first sample, not trace start; long-task t= offsets from the overview are relative to trace start. They usually differ by <1s but eyeball the sample span line.
Trace timestamps are microseconds.

---name: electron-profiledescription: Use when analyzing a Chrome/Electron DevTools Performance trace export (.json) — slow renders, long tasks, jank, CPU sample attribution, "where is the time actually going".---# DevTools Performance Trace AnalysisParse DevTools Performance panel exports with Python scripts in `scripts/` — no DevTools UI needed. A trace is one big JSON of `traceEvents`; a 400MB export loads in ~30s. The embedded sampling profile lives in `Profile`/`ProfileChunk` events.## Workflow1. **Overview** — processes, busiest renderer main thread, long tasks (with time offsets), X-event category totals: ```bash python3 scripts/trace-overview.py <trace.json> [--long-ms 50] [--top 30] ```2. **Sample attribution** — self time, inclusive time, and nearest-app-frame attribution from the CPU sampling profile. Use `--window` (seconds, relative to first sample) to zoom into a long task found in step 1: ```bash python3 scripts/trace-samples.py <trace.json> [--window FROM_S TO_S] [--top 30] ```Both auto-pick the busiest `CrRendererMain`; override with `--pid`/`--tid`. Both need `scripts/tracelib.py` alongside.## Interpreting results (dev builds especially)Dev-build traces are ~85-90% React dev instrumentation, NOT app code. Absolute numbers are meaningless; prod is ~10x faster. For real numbers profile the prod bundle (see prod-bundles skill), or at minimum disable the React DevTools extension while recording.| Signal | Meaning ||---|---|| Huge `run (:-1)` self time, `createTask`, `measure` | React 19 dev component-performance tracks: `console.createTask().run()` inside `runWithFiberInDEV`/`logComponentRender`. Not app code. || `v8::Debugger::AsyncTaskRun` dominating X-event totals | Debugger async-stack tracking (DevTools open). Dev artifact. || Effects firing twice back-to-back | StrictMode double-invoke. Dev only. || 90%+ samples with no app frame on stack | Expected in dev — instrumentation + framework internals. Judge the app-frame report's *relative* ranking, not totals. || `performSyncWorkOnRoot` ≫ scheduler time in inclusive report | Most renders are sync (flushSync / discrete events), not concurrent. Structural signal — valid even in dev. || `pptr:internal` frames | CDP automation harness driving the app, not app code (excluded from app-frame report). || Layout / Paint / GC / EventDispatch totals in overview | Real browser work — valid signal even in dev. Compare against script time. |**Judge structure, not magnitude** in dev traces: sync-vs-concurrent split, Layout/Paint/GC share, which app components rank highest, burst patterns around long tasks.## Gotchas- X-event name totals are nested-inclusive (parent contains child) — relative shape only, don't sum.- Sample span < trace span is normal: sampling only covers the profiled window.- App-frame attribution skips frames whose URL contains `node_modules` — with Vite dev this automatically excludes React (`node_modules/.vite/deps/...`).- `--window` is relative to the first *sample*, not trace start; long-task `t=` offsets from the overview are relative to trace start. They usually differ by <1s but eyeball the sample span line.- Trace timestamps are microseconds.

Frequently asked questions

Electron Profile