# Advanced Docs

These features are useful, but they are not required to adopt oagen as a framework.

Use this section when you need to preserve an existing SDK surface, verify behavior with smoke tests, or integrate generated files into a live SDK tree.

- [Workflows](../architecture/workflows.md)
- [Extractor Contract](../architecture/extractor-contract.md)
- [Non-Additive Changes](../architecture/non-additive-changes.md)
- [`@oagen-ignore` — Preserving Hand-Written Code](./oagen-ignore.md)
- [`transformSpec` — Pre-IR Spec Overlay](./transform-spec.md)
- [CLI Reference](../cli.md)