# Hyperfine — Command-Line Benchmarking Tool

> Hyperfine is a command-line benchmarking tool written in Rust. Run benchmarks with statistical analysis: multiple runs, warmup, outlier detection, comparison across commands, and export results. By the author of bat and fd.

## Install

Save the content below to `.claude/skills/` or append to your `CLAUDE.md`:

## Quick Use

```bash
brew install hyperfine                      # macOS
cargo install hyperfine                     # Rust
sudo apt install hyperfine                  # Debian/Ubuntu
```

```bash
# Basic benchmark
hyperfine "sleep 0.5"

# Compare two commands
hyperfine "fd pattern" "find . -name pattern"

# With warmup runs
hyperfine --warmup 3 "cargo build"

# Multiple commands with labels
hyperfine \
  -n ripgrep "rg pattern" \
  -n grep "grep -r pattern ."

# Export results
hyperfine --export-markdown results.md "rg pattern" "grep -r pattern ."
hyperfine --export-json results.json "command"

# Parameter scan
hyperfine --parameter-scan threads 1 8 "cargo build -j {threads}"

# Preparation command (runs before each)
hyperfine --prepare "sync; echo 3 | sudo tee /proc/sys/vm/drop_caches" "cat large_file"
```

## Intro

Hyperfine is a command-line benchmarking tool written in Rust by David Peter (also author of bat, fd, and pastel). Runs a command multiple times, performs statistical analysis, detects outliers, and outputs clean formatted results. The standard tool for CLI benchmarking.

- **Repo**: https://github.com/sharkdp/hyperfine
- **Stars**: 27K+
- **Language**: Rust
- **License**: Apache 2.0 + MIT

## What Hyperfine Does

- **Multiple runs** — statistical significance (mean, stddev, min, max)
- **Warmup** — configurable warmup runs before measurement
- **Outlier detection** — flags and handles statistical outliers
- **Comparison** — benchmark multiple commands side by side
- **Parameter scan** — sweep a variable across values
- **Preparation** — run setup before each benchmark iteration
- **Export** — Markdown, JSON, CSV, AsciiDoc
- **Shell** — configurable shell or no shell
- **Progress bar** — visual progress during runs

## Comparison

| Tool | Statistical | Multi-cmd | Export |
|---|---|---|---|
| Hyperfine | Full | Yes | MD/JSON/CSV |
| time (shell) | None | No | No |
| bench (Go) | Basic | No | No |
| poop (Zig) | Full | Yes | Terminal |

## FAQ

**Q: How many runs are needed?**
A: By default it decides automatically (at least 10 runs or 3 seconds). Add `--min-runs 50` or `--max-runs 100` for precise control.

**Q: How to eliminate cache effects?**
A: Use `--prepare` to clear caches before each run, or `--warmup 5` to let caches stabilize before timing.

## Sources

- GitHub: https://github.com/sharkdp/hyperfine
- License: Apache 2.0 + MIT

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Source: https://tokrepo.com/en/workflows/hyperfine-command-line-benchmarking-tool-ce6e174e
Author: Script Depot