🚀 Crossplane Platform Toolkit

A modular, scalable, and production-ready toolkit for managing AWS cloud infrastructure — EKS, RDS, S3, and beyond — using Crossplane and native Kubernetes APIs.

---

📖 About

The Crossplane Platform Toolkit delivers a standardized, self-service approach to provisioning and managing AWS infrastructure using Infrastructure-as-Code (IaC) principles — entirely within Kubernetes.

Rather than relying on traditional CLI tools, Terraform, or scattered CloudFormation templates, this toolkit harnesses the power of Crossplane Compositions to transform cloud infrastructure into first-class Kubernetes objects. Platform teams define the guardrails; application teams provision what they need — with just a YAML claim.

Key Benefits:

• 🏗️ Platform Engineering First — Abstracts AWS complexity behind clean, opinionated Kubernetes APIs
• 🔁 GitOps Ready — Every resource is declarative, versionable, and auditable
• 🔒 Policy by Design — Enforce organizational standards (Free Tier limits, tagging, naming conventions) at the composition layer
• ⚡ Self-Service — Developers claim infrastructure without needing AWS console access
• 🧩 Modular — Each XRD is independently composable and reusable across environments

---

🏛️ Architecture

This toolkit is built on the Crossplane Control Plane pattern.

Developer submits Claim (YAML)
        │
        ▼
┌─────────────────────────┐
│  CompositeResource (XR) │  ← Created automatically by Crossplane
│  devops.murali.io/v1    │
└────────────┬────────────┘
             │  resolved by
             ▼
┌─────────────────────────┐
│     Composition         │  ← go-templating pipeline (function-go-templating)
│  (go-template engine)   │
└────────────┬────────────┘
             │  renders
             ▼
┌────────────────────────────────────────────┐
│         Managed Resources (AWS)            │
│  RDS Instance │ EKS Cluster │ VPC │ S3 ... │
└────────────────────────────────────────────┘

Custom API Group: devops.murali.io

XRD	Claim Kind	Description
xrdsinstances	RDSInstance	RDS PostgreSQL / MySQL (Free Tier ready)
xekscluster	EKSCluster	Managed EKS with node groups
xnetworks	Network	VPC, Subnets, NAT Gateway
xsecuritygroups	SecurityGroup	Bastion, EKS, DB security groups

---

✅ Prerequisites

Before deploying this toolkit, ensure you have the following in place:

Requirement	Version	Notes
Kubernetes Cluster	1.27+	EKS, Kind, or any CNCF-conformant cluster
Crossplane	1.14+	Installed via Helm
provider-aws (Upbound)	Latest	Configured with valid IAM credentials
function-go-templating	v0.4.0+	Required for all compositions
function-auto-ready	Latest	Pipeline step for readiness tracking
kubectl	1.27+	Configured against your target cluster

IAM Permissions

The AWS provider requires an IAM role or user with permissions to manage the target services (EC2, RDS, EKS, S3, IAM). It is recommended to use IRSA (IAM Roles for Service Accounts) in production.

---

🚀 Getting Started

1. Install Crossplane

helm repo add crossplane-stable https://charts.crossplane.io/stable
helm repo update

helm install crossplane crossplane-stable/crossplane \
  --namespace crossplane-system \
  --create-namespace

2. Install Required Functions

# function-go-templating
kubectl apply -f https://raw.githubusercontent.com/crossplane-contrib/function-go-templating/main/package/crds/

# Install via Crossplane package
kubectl apply -f - <<EOF
apiVersion: pkg.crossplane.io/v1beta1
kind: Function
metadata:
  name: function-go-templating
spec:
  package: xpkg.upbound.io/crossplane-contrib/function-go-templating:v0.4.0
---
apiVersion: pkg.crossplane.io/v1beta1
kind: Function
metadata:
  name: function-auto-ready
spec:
  package: xpkg.upbound.io/crossplane-contrib/function-auto-ready:v0.2.1
EOF

3. Configure AWS Provider

kubectl apply -f - <<EOF
apiVersion: pkg.crossplane.io/v1
kind: Provider
metadata:
  name: provider-aws
spec:
  package: xpkg.upbound.io/upbound/provider-aws:latest
EOF

4. Apply XRDs and Compositions

# Apply all definitions first
kubectl apply -f definitions/

# Then apply compositions
kubectl apply -f compositions/

5. Submit a Claim

# Create a Free Tier PostgreSQL instance
kubectl apply -f examples/rds-postgres.yaml

# Create a Free Tier MySQL instance
kubectl apply -f examples/rds-mysql.yaml

# Create an EKS cluster
kubectl apply -f examples/eks-cluster.yaml

6. Monitor Provisioning

# Check claim status
kubectl get rdsinstance -n <your-namespace>

# Check composite resource
kubectl get xrdsinstance

# Describe for detailed events
kubectl describe rdsinstance <name> -n <your-namespace>

# Watch all managed resources
kubectl get managed

---

📁 Project Structure

.
├── definitions/                        # CompositeResourceDefinitions (XRDs)
│   ├── xrd-rds-instance.yaml           # RDS PostgreSQL / MySQL XRD
│   ├── xrd-eks-cluster.yaml            # EKS Cluster XRD
│   ├── xrd-network.yaml                # VPC / Subnet / NAT XRD
│   └── xrd-security-group.yaml         # Security Group XRD
│
├── compositions/                       # Crossplane Compositions (go-templating)
│   ├── composition-rds-instance.yaml   # RDS composition (engine branching)
│   ├── composition-eks-cluster.yaml    # EKS composition (node group loop)
│   ├── composition-network.yaml        # Network composition (subnet array)
│   └── composition-security-group.yaml # SG composition (rule loop)
│
├── examples/                           # Claim examples (ready to apply)
│   ├── rds-postgres.yaml               # Free Tier PostgreSQL claim
│   ├── rds-mysql.yaml                  # Free Tier MySQL claim
│   ├── eks-cluster.yaml                # EKS cluster claim
│   └── network.yaml                    # VPC + subnet claim
│
├── docs/                               # Design docs & architecture notes
│   ├── architecture.md
│   ├── rds-design.md
│   └── eks-design.md
│
└── README.md

---

🔧 Design Principles

Principle	Implementation
Reference, don't recreate	Existing VPCs, subnets, and security groups are passed by ID — the toolkit never creates duplicate network resources
Engine branching in one Composition	A single engine: postgresql or engine: mysql parameter drives the entire composition branch
Free Tier by default	db.t3.micro, gp2, 20 GiB, single-az are defaults — upgrade paths are explicitly opt-in
No hardcoded values	Region, AZ, instance class, storage, and tags are all parameterized
Consistent API group	All XRDs live under devops.murali.io for clear ownership and discovery

---

🤝 Contributing

Contributions are welcome! Here's how to get started:

1. Fork this repository
2. Create a branch for your feature or fix:

   git checkout -b feature/add-s3-composition

3. Make your changes — add XRDs, compositions, or example claims
4. Test locally using crossplane beta render or a Kind cluster
5. Commit and push, then open a Pull Request with a clear description

Please ensure new compositions follow the existing patterns:

• Use function-go-templating with inline templates
• Include function-auto-ready as the final pipeline step
• Add a corresponding example claim under examples/
• Document any new XRD parameters in docs/

---

Built with ❤️ using Crossplane · Kubernetes · AWS