kubernetes-sigs/kustomize
Kustomize
Kustomize is a declarative configuration manager and manifest customizer for Kubernetes. It functions as a patching engine that transforms base YAML files into environment-specific configurations through overlays and composition, allowing for the generation of complex deployments without modifying original source files.
The tool distinguishes itself by using an overlay-based resource composition model to layer environment overrides on top of shared bases. It employs strategic merge patching and recursive base resolution to flatten inherited configurations into a final output set.
The project provides capabilities for resource generation, including the creation of secrets and configuration maps from local files. It supports container image updating, runtime variable injection, and extensibility through a plugin system that integrates external functions for resource transformation and validation.
The tool also integrates with remote sources to fetch configuration data and assets from external URLs or charts.
Features
- Overlay-Based Resource Composition - Layers environment-specific modifications on top of a common base configuration to generate final manifests without altering original files.
- Declarative Configuration - Provides a declarative framework for customizing Kubernetes resources while preserving the original source files.
- JSON Patching - Implements standard JSON patching and strategic merge operations to modify Kubernetes resource attributes.
- Configuration Base Composition - Combines multiple base resources and shared components to build complex, multi-variant deployment configurations.
- Configuration Component Composition - Builds complex deployment sets by combining multiple base resources and shared components into a single configuration.
- Configuration Overrides - Customizes base YAML resource files with environment-specific configurations without altering original source files.
- Configuration Overlays - Provides a mechanism for layering environment-specific overrides on top of common Kubernetes base configurations.
- Deployment Environment Management - Creates environment-specific application variants for development, staging, and production using overlays.
- Environment Configuration Management - Creates environment-specific variants by layering modifications over a common base configuration.
- Kubernetes Manifest Management - Manages YAML configuration files for Kubernetes clusters by applying patches and overrides to shared bases.
- Manifest Customizers - Transforms base Kubernetes YAML files into environment-specific configurations through overlays and patches.
- Manifest Generators - Produces final YAML output by processing declaration files and associated resources for deployment.
- Strategic Merge Patching - Merges YAML resources by matching specific keys and lists to update or append fields instead of replacing entire blocks.
- YAML Patching Engines - Applies JSON patches and strategic merges to Kubernetes resources without modifying original source files.
- Patch-Based Configuration Overrides - Applies environment-specific overrides to base YAML resource files without modifying original source templates.
- Customizations - Applies patches and transformations to raw YAML files to produce a final configuration without modifying original sources.
- Declarative Configuration Managers - Functions as a centralized manager for composing complex Kubernetes deployments via declarative structures.
- Manifest Transformations - Processes raw YAML files through discrete modifiers to produce a final desired state for deployment.
- Environment Configurations - Composes multiple configuration variants from a common base to deploy applications across different environments.
- Go-Based Plugins - Integrates custom Go-based logic to transform resources or generate configurations using a plugin system.
- Custom Configuration Functions - Implements custom generators and transformers through external functions to modify resources beyond built-in capabilities.
- ConfigMap and Secret Generators - Generates Kubernetes ConfigMaps and Secrets from files or plugins with support for rolling updates.
- Container Images - Provides automated mechanisms to update container image names and tags across multiple deployment manifests.
- Container Image Versioning - Updates container image tags and names across multiple manifests without requiring manual edits.
- Kubernetes Resource Generators - Creates ConfigMaps and Secrets from local files or plugins during the manifest build process.
- Manifest Value Modifiers - Injects string values into resource fields and updates image names without modifying base files.
- Extensible Plugin Architectures - Executes external binaries via a standard interface to transform resources or generate content during the build process.
- Resource Generator Plugins - Integrates custom generator and transformer plugins to produce resource content from external sources.
- Recursive Configuration Resolution - Traverses a tree of resource references to flatten multiple layers of inherited configurations into a single output set.
- Continuous Delivery and GitOps - Tool for customizing Kubernetes YAML configurations.
- Kubernetes Ecosystem - Customizes Kubernetes configurations without modifying templates.
