# Perf

> >-

- **Type:** Skill
- **Install:** `agentstack add skill-rube-de-cc-skills-perf`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [rube-de](https://agentstack.voostack.com/s/rube-de)
- **Installs:** 0
- **Category:** [Communication](https://agentstack.voostack.com/c/communication)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [rube-de](https://github.com/rube-de)
- **Source:** https://github.com/rube-de/cc-skills/tree/main/plugins/dlc/skills/perf

## Install

```sh
agentstack add skill-rube-de-cc-skills-perf
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# DLC: Performance Analysis

Run performance checks against the current project and create a GitHub issue with findings.

Before running, **read [../dlc/references/ISSUE-TEMPLATE.md](../dlc/references/ISSUE-TEMPLATE.md) now** for the issue format, and **read [../dlc/references/REPORT-FORMAT.md](../dlc/references/REPORT-FORMAT.md) now** for the findings data structure.

## Step 1: Identify Performance-Sensitive Areas

Scan the project to determine which performance checks are applicable:

| Indicator | Check Type | Tools |
|-----------|-----------|-------|
| `webpack.config.*` / `vite.config.*` / `next.config.*` | Bundle analysis | `webpack-bundle-analyzer`, `vite-bundle-analyzer`, `@next/bundle-analyzer` |
| `lighthouse` in deps or CI config | Lighthouse | `lighthouse` CLI |
| `bench` / `benchmark` dirs or scripts | Benchmarks | Project-specific (e.g. `vitest bench`, `cargo bench`, `go test -bench`) |
| `docker-compose*` / `Dockerfile` | Container analysis | `dive`, `docker image inspect` |
| `tsconfig.json` / `package.json` (with build scripts) | Build time | Time the build command |

## Step 2: Run Performance Tools

### Bundle Analysis (Web Projects)

Select the tool based on detected build config — run only the first matching tool:

```bash
# Detect bundler and run the matching analysis
if [ -f webpack.config.js ] || [ -f webpack.config.ts ]; then
  npx webpack --json 2>/dev/null | jq '.assets[] | {name, size}'
elif [ -f vite.config.js ] || [ -f vite.config.ts ]; then
  npx vite build --report 2>/dev/null
elif [ -f next.config.js ] || [ -f next.config.mjs ]; then
  ANALYZE=true npx next build 2>/dev/null
fi
```

### Lighthouse (Web Projects)

```bash
# If lighthouse CLI available and there's a dev server or static build
lighthouse http://localhost:3000 --output=json --quiet 2>/dev/null
```

### Benchmarks

```bash
# Node.js
npx vitest bench --reporter=json 2>/dev/null

# Rust
cargo bench 2>/dev/null

# Go
go test -bench=. -benchmem ./... 2>/dev/null

# Python
python -m pytest --benchmark-only 2>/dev/null
```

### Build Time Analysis

```bash
# Time the build
time npm run build 2>&1
# or
time cargo build --release 2>&1
```

### Claude Algorithmic Analysis (Always Run)

Even with tools, always perform manual analysis. Use the Explore agent to discover performance-sensitive areas across the codebase (hot paths, data pipelines, request handlers). Use repomix-explorer (if available) for large codebases to get a structural overview. Then use targeted Grep and Read for detailed analysis:
- Search for `O(n^2)` or worse patterns: nested loops over the same collection, repeated array searches
- Check for missing indexes in database queries (`*.sql`, ORM query files)
- Look for synchronous blocking in async contexts
- Identify N+1 query patterns in data-fetching code
- Check for unbounded data structures (lists that grow without limit)
- Review hot paths: request handlers, event loops, data pipelines

## Step 3: Classify Findings

Map results to the findings format from REPORT-FORMAT.md.

**Severity mapping** (reinforced here for defense-in-depth):

| Finding Type | Severity |
|-------------|----------|
| Bundle size regression > 50% | **Critical** |
| O(n^3) or worse in hot path | **Critical** |
| Lighthouse performance score  project target | **Medium** |
| Missing database indexes on queried columns | **Medium** |
| Synchronous blocking in async context | **Medium** |
| Minor optimization opportunities | **Low** |
| Benchmark results (informational) | **Info** |

## Step 4: Create GitHub Issue

**Read [../dlc/references/ISSUE-TEMPLATE.md](../dlc/references/ISSUE-TEMPLATE.md) now** and format the issue body exactly as specified.

**Critical format rules** (reinforced here):
- Title: `[DLC] Performance: {summary of top finding}`
- Label: `dlc-perf`
- Body must contain: Scan Metadata table, Findings Summary table (severity x count), Findings Detail grouped by severity, Recommended Actions, Raw Output in collapsed details

```bash
REPO=$(gh repo view --json nameWithOwner -q .nameWithOwner)
BRANCH=$(git branch --show-current)
TIMESTAMP=$(date +%s)
BODY_FILE="/tmp/dlc-issue-${TIMESTAMP}.md"

gh issue create \
  --repo "$REPO" \
  --title "[DLC] Performance: {summary}" \
  --body-file "$BODY_FILE" \
  --label "dlc-perf"
```

If issue creation fails, save draft to `/tmp/dlc-draft-${TIMESTAMP}.md` and print the path.

## Step 5: Report

```text
Performance analysis complete.
  - Checks run: {list of applicable checks}
  - Tools used: {list}
  - Findings: {critical} critical, {high} high, {medium} medium
  - Issue: #{number} ({url})
```

If no findings, skip issue creation and report: "No performance issues found."

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [rube-de](https://github.com/rube-de)
- **Source:** [rube-de/cc-skills](https://github.com/rube-de/cc-skills)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-rube-de-cc-skills-perf
- Seller: https://agentstack.voostack.com/s/rube-de
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.