What Crossplane Does#

Crossplane extends Kubernetes to provision and manage cloud infrastructure using the Kubernetes API. Instead of writing Terraform and running apply, you write Kubernetes manifests and kubectl apply them. Crossplane controllers reconcile the desired state with the actual cloud resources.

The real value is not replacing Terraform — it is building abstractions. Platform teams define custom resource types (like DatabaseClaim) that developers consume without knowing whether they are getting RDS, CloudSQL, or Azure Database. The composition layer maps the simple claim to the actual cloud resources.

Advanced GitHub Actions Patterns#

Once you understand the basics of GitHub Actions, these patterns solve the real-world problems: testing across multiple environments, authenticating to cloud providers without static secrets, building reusable action components, and scaling runners.

Matrix Builds#

Test across multiple OS versions, language versions, or configurations in parallel:

jobs:
  test:
    strategy:
      fail-fast: false
      matrix:
        os: [ubuntu-latest, macos-latest]
        go-version: ['1.22', '1.23']
    runs-on: ${{ matrix.os }}
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-go@v5
        with:
          go-version: ${{ matrix.go-version }}
      - run: go test ./...

This creates 4 jobs (2 OS x 2 Go versions) running in parallel. Set fail-fast: false so a failure in one combination does not cancel the others – you want to see all failures at once.

Cross-Border Data Transfer#

Moving personal data across national borders is routine in distributed systems — a European user’s request hits a CDN edge in Frankfurt, the application runs in us-east-1, logs ship to a monitoring SaaS in the US, and backups replicate to ap-southeast-1. Each of these data movements is a cross-border transfer that may require legal justification and technical safeguards.

GDPR is the most impactful framework for cross-border transfers, but similar requirements exist in Brazil (LGPD), Canada (PIPEDA), South Korea (PIPA), Japan (APPI), and others. This guide focuses on GDPR as the reference model because most other frameworks follow similar principles.

Data Classification and Handling#

Data classification assigns sensitivity levels to data and maps those levels to specific handling requirements — who can access it, how it is encrypted, where it can be stored, how long it is retained, and how it is disposed of. Without classification, every piece of data gets the same (usually insufficient) protection, or security is applied inconsistently based on individual judgment.

Defining Classification Tiers#

Most organizations need four tiers. Fewer leads to overly broad categories. More leads to confusion about which tier applies.

Data Sovereignty and Residency#

Data sovereignty is the principle that data is subject to the laws of the country where it is stored or processed. Data residency is the requirement to keep data within a specific geographic boundary. These are not abstract legal concepts — they dictate where you deploy infrastructure, how you replicate data, and what services you can use.

Get this wrong and the consequences are regulatory fines, contract violations, and loss of customer trust. GDPR fines alone have exceeded billions of euros since enforcement began.

Multi-Cloud vs Single-Cloud Strategy#

Multi-cloud is one of the most oversold strategies in infrastructure. Vendors, consultants, and conference speakers promote it as the default approach, but the reality is that most organizations are better served by a single cloud provider used well. This framework helps you determine whether multi-cloud is actually worth the cost for your situation.

The Default Answer Is Single-Cloud#

Start with single-cloud unless you have a specific, concrete reason to go multi-cloud. Here is why.

Regulatory Compliance Frameworks#

Regulatory compliance translates legal requirements into technical controls. Understanding which regulations apply to your system and mapping them to infrastructure and application design is a core engineering responsibility in regulated industries.

This guide covers four major frameworks and their practical implications for software architecture. These are not exhaustive compliance guides — they map the most impactful technical controls for each framework.

HIPAA (Health Insurance Portability and Accountability Act)#

HIPAA applies to organizations handling Protected Health Information (PHI) — any data that can identify a patient and relates to their health condition, treatment, or payment.