# Storage Variant Guide

> Guide for implementing features across all storage variants. Use when the user is adding or modifying storage layer functionality.

- Skill: `apicurio/storage-variant-guide` (Agent Skill)
- Install (CLI): `npx skillmds@latest add apicurio/storage-variant-guide`
- Raw SKILL.md: https://api.skillmd.com/api/skills/apicurio/storage-variant-guide/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: apicurio (https://skillmd.com/u/apicurio)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/apicurio/storage-variant-guide

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# Storage Variant Implementation Guide

When implementing a feature that touches the storage layer:

1. **Start with SQL** (`app/src/.../storage/impl/sql/`) — this is the canonical implementation
2. **Adapt for KafkaSQL** (`app/src/.../storage/impl/kafkasql/`) — uses a Kafka journal pattern;
   state changes are serialized as Kafka messages and replayed
3. **Consider GitOps** (`app/src/.../storage/impl/gitops/`) — file-based, git-backed
4. **Consider KubernetesOps** (`app/src/.../storage/impl/kubernetesops/`) — ConfigMap-based
5. **Update RegistryStorage interface** if adding new operations
6. **Update decorators** (`storage/decorator/`) if the feature needs cross-cutting behavior
7. **DTOs must be serializable** — KafkaSQL journals serialize them
8. **Test with at least SQL and KafkaSQL** integration test profiles