ADR 0001 — Use Go and Kubebuilder¶

Status: Accepted
Date: August 2026

Context¶

The Trussium Operator must define Kubernetes APIs, watch custom resources, reconcile owned resources, report status, and integrate with Kubernetes-native testing and packaging workflows.

Decision¶

The operator will be implemented in Go using:

Kubebuilder
controller-runtime
controller-tools
Kustomize
envtest
Kind

The repository will use the Kubebuilder go/v4 project layout.

Rationale¶

Go and controller-runtime provide direct access to Kubernetes API machinery and the established reconciliation model used by Kubernetes controllers.

Kubebuilder provides consistent scaffolding for:

API types
Controllers
RBAC generation
CRD generation
Manager deployment
Health endpoints
Testing
Tool-version management

Consequences¶

Positive¶

Strong alignment with Kubernetes conventions
Typed API definitions
Mature controller testing
Generated RBAC and CRD assets
Straightforward access to Kubernetes libraries

Negative¶

The operator uses a different language from the Python Trussium runtime.
Contributors must understand Kubernetes API conventions and generated code.
Kubernetes dependency upgrades require compatibility management.

Follow-Up¶

The operator and runtime communicate through container, configuration, health, and Kubernetes contracts rather than sharing implementation code.