erne-perf

AI Community

Repo stars 36
License MIT
Author repo everything-react-native-expo

Interpretation is structured for decision-making; original keeps the upstream SKILL.md unchanged.

Decide Fit First

Core job: ERNE — Performance profiling and optimization using the performance-profiler agent You are executing the /erne-perf command. Use…
Best fit: Use it when the task has reusable inputs, steps, and validation criteria rather than a one-off answer.
Avoid forcing it: If the source lacks commands, platform support, or external-service evidence, keep those fields unknown instead of guessing.

Design Intent

Structure: The skill is organized around “Diagnostic Areas”, “1. Rendering Performance (FPS)”, “2. Time to Interactive (TTI)”, “3. Bundle Size”, showing how the author expects the agent to judge fit, collect context, and produce verifiable output.
Trigger evidence: Prioritize the author’s wording around when to use it, what context to collect, and what output shape to produce.
Evidence boundary: Author text states facts, repository files prove commands and paths, and Fluxly only adds fit, limits, and usage judgment.

How To Use It

Inputs: Provide target material, scope, expected result, forbidden changes, and validation method.
Invocation: Name erne-perf directly; if the source includes slash commands, start with the command and then add task context.
Validation: Start small and check whether the result follows “Diagnostic Areas / 1. Rendering Performance (FPS) / 2. Time to Interactive (TTI)” before expanding.

Boundaries And Review

Dependencies: It usually needs no extra API key, so start with a small validation task.
Permissions: Declared permissions include read / shell-exec; ask the agent to state file, command, and rollback boundaries before acting.
Quality bar: A useful result names the deliverable, evidence, and next action. Generic prose means the task needs tighter context.

/erne-perf — Performance Profiling

You are executing the /erne-perf command. Use the performance-profiler agent to diagnose and fix performance issues.

Diagnostic Areas

1. Rendering Performance (FPS)

Check for unnecessary re-renders with React DevTools Profiler
Identify components re-rendering without prop changes
Look for missing React.memo, useCallback, useMemo
Detect inline function/object creation in render

2. Time to Interactive (TTI)

Analyze app startup sequence
Check for heavy useEffect chains on mount
Identify blocking operations on main thread
Verify Hermes bytecode compilation

3. Bundle Size

Run npx react-native-bundle-visualizer
Identify large dependencies
Check for unused imports and dead code
Verify tree-shaking is working

4. Memory

Check for listener/subscription cleanup in useEffect
Identify large objects retained in closures
Look for image caching issues
Detect circular references

5. Animations

Verify all animations use Reanimated (not Animated API)
Check for JS thread bottlenecks in animation callbacks
Identify layout thrashing during animations
Measure actual FPS during animations

6. Hermes Engine

Verify Hermes is enabled
Check for unsupported JS features
Profile with Hermes sampling profiler
Analyze bytecode compilation output

Output Format

## Performance Metrics
| Metric | Current | Target | Status |
|--------|---------|--------|--------|
| JS FPS | 45 | 60 | ⚠️ |
| UI FPS | 58 | 60 | ✅ |
| TTI | 3.2s | <2s | ❌ |
| Bundle | 8.2MB | <5MB | ❌ |

## Critical Issues
[Issues that must be fixed]

## Optimization Opportunities
[Improvements ranked by impact]

Notes

If agent-device is available, measure actual FPS on device
Reference rules/common/performance.md for optimization patterns
Profile on real devices, not simulator/emulator

Fluxly profile Author and license come from source; runtime, permissions, and network are Fluxly detections or estimates

Fluxly category: AI
Author-declared agents: No explicit declaration found; this is not inferred or tested compatibility
Static check: 94 / 100 · heuristic scan, not runtime safety proof
Author / version / license: @JubaKitiashvili · MIT
Fluxly token estimate: Lean
Fluxly setup estimate: Guided setup
External API key: No requirement detected
Detected OS requirements: macOS · Linux · Windows
Runtime requirements: Unspecified
Detected file/system behavior: Read-only
Shell exec
Detected network behavior: Local-only
Install commands: None (reference only)

Profile is derived at build time from SKILL.md and install vectors. Subject to drift from author intent.

Heads up: 未限定 allowed-tools，默认拥有全部工具权限。

Output preview erne-perf.preview

The current SKILL.md does not define a fixed output example.

SKILL.md SKILL.md

# /erne-perf — Performance Profiling

You are executing the `/erne-perf` command. Use the **performance-profiler** agent to diagnose and fix performance issues.

## Diagnostic Areas

### 1. Rendering Performance (FPS)
- Check for unnecessary re-renders with React DevTools Profiler
- Identify components re-rendering without prop changes
- Look for missing `React.memo`, `useCallback`, `useMemo`
- Detect inline function/object creation in render

### 2. Time to Interactive (TTI)
- Analyze app startup sequence
- Check for heavy `useEffect` chains on mount
- Identify blocking operations on main thread
- Verify Hermes bytecode compilation

### 3. Bundle Size
- Run `npx react-native-bundle-visualizer`
- Identify large dependencies
- Check for unused imports and dead code
- Verify tree-shaking is working

### 4. Memory
- Check for listener/subscription cleanup in `useEffect`
- Identify large objects retained in closures
- Look for image caching issues
- Detect circular references

### 5. Animations
- Verify all animations use Reanimated (not Animated API)
- Check for JS thread bottlenecks in animation callbacks
- Identify layout thrashing during animations
- Measure actual FPS during animations

### 6. Hermes Engine
- Verify Hermes is enabled
- Check for unsupported JS features
- Profile with Hermes sampling profiler
- Analyze bytecode compilation output

## Output Format
```
## Performance Metrics
| Metric | Current | Target | Status |
|--------|---------|--------|--------|
| JS FPS | 45 | 60 | ⚠️ |
| UI FPS | 58 | 60 | ✅ |
| TTI | 3.2s | <2s | ❌ |
| Bundle | 8.2MB | <5MB | ❌ |

## Critical Issues
[Issues that must be fixed]

## Optimization Opportunities
[Improvements ranked by impact]
```

## Notes
- If agent-device is available, measure actual FPS on device

…

Evidence boundary and execution chain

Author text anchors workflow facts; Fluxly only indexes current sections, terms, files, and commands.

sections -> Diagnostic Areas → 1. Rendering Performance (FPS) → 2. Time to Interactive (TTI) → 3. Bundle Size → 4. Memory → 5. Animations
terms    -> performance-profiler · You are executing the /erne-perf command.
files/cmd -> /erne-perf · React.memo · useCallback · useMemo · useEffect · npx react-native-bundle-visualizer · rules/common/performance.md
body sha256 -> 812306b99f9c