docs: add open-bao readme compatibilies overwiew

Author: SoulKyu

README.md

@@ -20,7 +20,20 @@ Contributions to the vault-db-injector are welcome. Please submit your pull requ
 
 Here you can find a comparison with many vault injector projects : [Comparaison](https://numberly.github.io/vault-db-injector/getting-started/comparison/)
 
-##  5. <a name='Acknowledgements'></a>Acknowledgements
+## 5. <a name='OpenBao'></a>OpenBao Compatibility
+
+The Vault DB Injector is fully compatible with OpenBao, a community-driven fork of HashiCorp Vault. Since OpenBao maintains API compatibility with Vault, you can seamlessly use this injector with your OpenBao installation without any code modifications.
+
+All the Vault APIs used by this project work out of the box with OpenBao, including:
+- Kubernetes authentication
+- Database secrets engine
+- Token management and renewal
+- KV v2 secrets engine for metadata storage
+- Lease management
+
+To use the injector with OpenBao, simply point the `vaultAddress` configuration to your OpenBao instance and ensure your OpenBao setup includes the necessary authentication backends, database engine configuration, and policies that match your deployment requirements.
+
+##  6. <a name='Acknowledgements'></a>Acknowledgements
 
 Special thanks to the contributors and maintainers of the project.