infrastructure

name	infrastructure
description	Use when editing Terraform, Kubernetes manifests, Helm charts, infrastructure modules, or deployment configuration.

Infrastructure Patterns

Terraform

Module Structure

• Use a standard layout: main.tf, variables.tf, outputs.tf, versions.tf
• Extract reusable patterns into modules under modules/
• Keep modules focused -- one resource group per module
• Use terraform-docs to auto-generate module documentation

State Management

• Always use remote state (S3, GCS, or Terraform Cloud)
• Enable state locking (DynamoDB for S3 backend)
• Use separate state files per environment
• Never commit .tfstate files to version control
• Use terraform import for existing resources, never recreate

Best Practices

• Pin provider versions in versions.tf
• Use terraform fmt and terraform validate in CI
• Run terraform plan in CI, apply only from CD pipeline
• Tag all resources with environment, team, and managed_by
• Use data sources to reference existing infrastructure
• Use locals for computed values, variables for inputs

Kubernetes

Resource Limits

• Always set requests and limits for CPU and memory
• requests = guaranteed minimum, limits = hard ceiling
• Start conservative and tune based on metrics
• Use LimitRange and ResourceQuota for namespace defaults

Probes

• livenessProbe: restart if unhealthy (checks process is alive)
• readinessProbe: remove from service if not ready (checks dependencies)
• startupProbe: allow slow-starting containers before liveness kicks in
• Use HTTP probes for web services, TCP for databases, exec for custom checks
• Set initialDelaySeconds based on actual startup time

Best Practices

• Use Deployment for stateless, StatefulSet for stateful workloads
• Define PodDisruptionBudget for high-availability services
• Use ConfigMap for config, Secret for sensitive data
• Set imagePullPolicy: IfNotPresent and use specific image tags
• Use namespaces to isolate environments and teams

Helm

Chart Best Practices

• Use values.yaml for defaults, override per environment
• Template helpers go in _helpers.tpl
• Include NOTES.txt for post-install instructions
• Use helm lint and helm template in CI
• Pin chart versions in Chart.lock
• Use subcharts for shared infrastructure (databases, caches)