Ytt

ytt Plugin

YAML templating tool that works on YAML structure instead of text. Template and patch YAML configurations with a powerful overlay mechanism.

Commands

Template Rendering

• ytt template render — Render YAML templates

Configuration Patching

• ytt config patch — Patch YAML configurations

Utility

• ytt _ _ — Passthrough to ytt CLI

Usage Examples

• "Template YAML files"
• "Patch Kubernetes config"
• "Render YAML templates"
• "Apply YAML overlays"

Installation

brew install ytt

Examples

# Render templates
ytt template render ./templates/

# With data values
ytt template render ./templates/ --data-values-file values.yaml

# Patch configurations
ytt config patch ./base.yaml ./overlay.yaml

# Output as JSON
ytt template render ./templates/ --output json

# Any ytt command with passthrough
ytt _ _ -f ./templates/
ytt _ _ -f ./config.yaml -f ./overlay.yaml

Key Features

• Structure - Works on YAML structure
• Templates - Powerful templating
• Overlays - Overlay mechanism
• Starlark - Starlark language
• Data values - External data values
• Functions - Custom functions
• Kubernetes - K8s configs
• Library - Reusable libraries
• Patching - Config patching
• Accurate - Text-safe editing

Notes

• Part of Carvel suite
• Works on structure not text
• Great for K8s configs
• Supports reusable libraries