kaioken

A Rust-based HTTP load testing tool with real-time terminal UI and DBZ flavor.

Features

• Real-time TUI - Live metrics with latency percentiles, RPS, status codes, and sparkline
• Rate limiting - Token bucket algorithm for controlled load (-r 1000)
• Ramp-up - Gradually activate workers over time (--ramp-up 10s)
• Warmup - Prime connections before measuring (--warmup 5s)
• Config files - TOML configuration with environment variable interpolation
• Multiple outputs - JSON, CSV, and Markdown formats
• Compare mode - Detect regressions between runs with CI-friendly exit codes
• DBZ flavor - Power levels from Farmer to OVER 9000 (toggleable with --serious)

Installation

cargo install kaioken

Quick Start

# Basic test
kaioken run https://api.example.com/health

# With options
kaioken run https://api.example.com/users \
  -c 100 \          # 100 concurrent workers
  -d 30s \          # 30 second duration
  -r 500 \          # 500 requests/sec max
  --warmup 5s       # 5 second warmup

# Headless mode for CI
kaioken run https://api.example.com --no-tui --format json -o results.json

# Compare two runs for regressions
kaioken compare baseline.json current.json

TUI Preview

┌─────────────────────────────────────────────────────────────────┐
│  KAIOKEN x100    https://api.example.com/users    [00:15/00:30] │
├───────────────────────────────────┬─────────────────────────────┤
│  POWER LEVEL                      │  LATENCY (ms)               │
│                                   │                             │
│  Rolling RPS: 8,432    [VEGETA]   │  p50:   12    ████          │
│  Total:       126,480             │  p90:   45    ██████████    │
│  Errors:      23 (0.02%)          │  p95:   89    ████████████  │
│                                   │  p99:  230    █████████████ │
│  ▁▂▃▅▆▇█▇▆▅▄▃▂▁▂▃▄▅▆▇            │  p999: 567    ██████████████│
├───────────────────────────────────┼─────────────────────────────┤
│  STATUS CODES                     │  ERRORS                     │
│                                   │                             │
│  200  ████████████████████  84012 │  timeout     15             │
│  201  ██                      312 │  connect      5             │
│  500  ▏                        23 │  reset        3             │
└───────────────────────────────────┴─────────────────────────────┘
  [q]uit  [s]ave  [?]help                              Running...

CLI Options

Config File

[target]
url = "https://api.example.com/users"
method = "POST"
timeout = "5s"

[target.headers]
Authorization = "Bearer ${API_TOKEN}"
Content-Type = "application/json"

[load]
concurrency = 100
duration = "30s"
rate = 500
warmup = "5s"

Environment variables are interpolated with ${VAR} or ${VAR:-default}.

Output Formats

JSON

kaioken https://example.com --json

CSV

kaioken https://example.com --no-tui --format csv

Markdown

kaioken https://example.com --no-tui --format md -o report.md

Power Levels

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.