crossplane

type	Skill
name	crossplane
title	Crossplane
description	Crossplane composition patterns for cloud-agnostic infrastructure as code. Use when writing Crossplane Compositions, XRDs (CompositeResourceDefinitions), or Claims, managing cloud resources declaratively from Kubernetes, or designing platform team infrastructure abstractions with Crossplane.
tags	["devops","crossplane","infrastructure","iac","kubernetes","cloud"]
timestamp	"2026-06-14T00:00:00.000Z"
id	skill-crossplane
cdr_ref	null
created	"2026-01-16T00:00:00.000Z"
modified	"2026-06-14T00:00:00.000Z"
verified	"2026-05-21T00:00:00.000Z"
age_days	149
evidence	[]
instruction_type	Generation
priority	Standard

Crossplane Skill

What This Skill Provides

Patterns for authoring Crossplane Compositions and XRDs that provide developer-facing infrastructure abstractions backed by cloud provider managed resources.

When to Use This Skill

• Writing Crossplane Compositions or XRDs
• Creating developer-facing composite resource Claims
• Designing platform team infrastructure abstractions
• Migrating Terraform resource definitions to Crossplane
• Debugging Composition or Claim reconciliation issues

Core Patterns

XRD > Composition > Claim Hierarchy

Rule: Define a clear three-layer hierarchy for each infrastructure domain.

Implementation:

• XRD: Defines the API schema (the "CRD for platform users")
• Composition: Maps XRD fields to one or more cloud provider managed resources
• Claim: What application teams use to request infrastructure
• Keep XRDs stable; evolve Compositions without breaking Claim consumers

References: See @rule:devops/crossplane_compositions.md

DRY Compositions with PatchSets

Rule: Avoid duplicating managed resource definitions across Compositions.

Implementation:

• Use patchSets for groups of patches applied to multiple resources
• Use transforms for value mapping rather than hardcoding environment-specific values
• Parameterize Compositions via XRD fields rather than forking per environment

References: See @rule:devops/crossplane_compositions.md

Composition Validation and Testing

Rule: Validate Compositions before applying to production clusters.

Implementation:

• Use crossplane beta validate to lint XRDs and Compositions
• Test Claim rendering in an isolated dev cluster before promoting
• Monitor Composition health via crossplane beta trace

References: See @rule:devops/crossplane_compositions.md