1. Architecture: AWS Controllers for Kubernetes focuses on managing AWS resources directly from Kubernetes using Custom Resource Definitions (CRDs) and controllers, allowing seamless integration between Kubernetes clusters and AWS services. Velero, on the other hand, is a backup and restore tool that helps in taking snapshots of Kubernetes cluster resources and persistent volumes, enabling disaster recovery and migration capabilities.
2. Use Case: AWS Controllers for Kubernetes is ideal for applications that heavily rely on AWS services for tasks such as storage, networking, databases, and more, integrating them with Kubernetes seamlessly. Velero, on the contrary, is more suited for backup and recovery use cases to safeguard Kubernetes cluster data and resources in case of failures, corruption, or accidental deletions.
3. Control and Management: While AWS Controllers for Kubernetes offer direct control and management capabilities of AWS resources within Kubernetes environments, Velero primarily focuses on data protection and recovery, providing backup, restore, and migration functionalities for Kubernetes applications and resources.
4. Integration with AWS Services: AWS Controllers for Kubernetes enables bi-directional synchronization with AWS services, constantly updating the status of resources within Kubernetes to match the actual state in AWS. Velero, however, operates independently of AWS services, focusing solely on backup and restore operations within Kubernetes clusters.
5. Scaling and Automation: AWS Controllers for Kubernetes provides the ability to automatically manage and scale AWS resources based on Kubernetes workload demands, ensuring efficient resource utilization and dynamic scaling. Velero, in contrast, is more manual in nature and requires user intervention for initiating backup and recovery processes.
6. Community Support and Adoption: The AWS Controllers for Kubernetes project is actively developed and supported by AWS with contributions from the Kubernetes community, ensuring ongoing improvements, updates, and compatibility with AWS services. Velero, while also well-maintained, mainly receives contributions and updates from the open-source community, providing a robust backup and recovery solution for Kubernetes users.

In Summary, the key differences between AWS Controllers for Kubernetes and Velero lie in their architectures, use cases, control and management capabilities, integration with AWS services, scaling and automation features, and the level of community support and adoption they receive.