During July 2025, Casper Smits enhanced the Shopify/rails repository by addressing a backend reliability issue related to query string key validation. He implemented robust encoding checks for query string keys, ensuring they matched the existing validation for values and preventing malformed or invalid UTF-8 input from reaching business logic. By introducing BadRequest responses for requests with improperly encoded keys and expanding end-to-end test coverage, Casper reduced the risk of downstream failures and improved server-side security. His work, using Ruby and Ruby on Rails, demonstrated careful attention to input validation and contributed to the overall resilience of the backend system.