Worked on enhancing DynamoDB support in both the hashicorp/terraform-provider-aws and opentofu/terraform-provider-aws repositories, focusing on backend reliability and maintainability. Expanded the DynamoDB Global Secondary Index testing framework, adding comprehensive test cases for create, update, and delete operations using Go and Terraform. Addressed critical bugs, including inconsistencies in GSI updates and attribute validation when table names are determined post-apply, reducing failure rates and improving diagnostics. Improved code quality through linting and documentation updates, ensuring compliance and readability. Strengthened test coverage by refactoring test names and adding existence checks, resulting in more robust validation and streamlined production deployments.