cryload - Powerful HTTP Benchmarking Tool

cryload is a powerful, fast, and practical HTTP benchmarking tool for stress testing APIs and web services.

Built with Crystal for high performance and low overhead.

Why cryload?

• High-throughput HTTP load testing with a lightweight CLI experience
• Concurrent benchmarking with configurable connection count
• Request count mode (-n) and duration mode (-d) support
• Flexible request customization (method, headers, body, timeout, TLS)
• JSON output mode for CI/CD and automation workflows

Installation

Option 1: Prebuilt binary (recommended)

Download the latest prebuilt binary from the Releases page, then make it executable:

chmod +x cryload
./cryload --help

Option 2: Build from source

Requires Crystal 1.19.0 or later.

git clone https://github.com/sdogruyol/cryload.git && cd cryload
shards build --release

The binary will be at bin/cryload.

Quick Start

Run your first benchmark in seconds:

bin/cryload http://localhost:3000 -n 10000 -c 100

Usage

cryload <url> [options]

Options:

Examples:

10,000 requests to localhost

cryload http://localhost:9292 -n 10000

10 seconds with 100 connections

cryload http://localhost:3000 -d 10 -c 100

Simple POST request

cryload http://localhost:3000/api/login -n 1000 -m POST

POST with plain text body

cryload http://localhost:3000/api/echo -n 500 -m POST -H "Content-Type: text/plain" -b "hello"

POST with JSON body

cryload http://localhost:3000/api -n 500 -m POST -H "Content-Type: application/json" -b '{"name":"cry"}' --timeout 5

POST with multiple headers

cryload http://localhost:3000/api -n 300 -m POST -H "Authorization: Bearer token123" -H "X-Request-ID: benchmark-1" -b '{"ok":true}'

Duration mode + timeout

cryload http://localhost:3000/api -d 15 -c 50 --timeout 3

HTTPS with self-signed cert (skip TLS verification)

cryload https://localhost:8443 -n 1000 --insecure

JSON output for automation/CI

cryload http://localhost:3000/api -n 1000 --json

Example output:

Preparing to make it CRY for 10 seconds with 100 connections!
Running load test @ http://localhost:3000/

  Latency (ms)      avg: 0.53   stdev: 0.76   max: 35.39

  Percentiles (ms)  p95: 0.96   p99: 1.34

1696170 requests in 10.11s
Requests/sec:  167803.62
2xx: 1696170    Non-2xx: 0

Built With Crystal

cryload is written in Crystal, combining Ruby-like developer ergonomics with compiled-language speed.

Contributing

1. Fork the repo
2. Create your feature branch (git checkout -b my-feature)
3. Commit your changes (git commit -am 'Add feature')
4. Push to the branch (git push origin my-feature)
5. Open a Pull Request

License

MIT