Worked on the cloudflare/workerd repository to deliver foundational TypeScript type definitions and interfaces supporting media input, binding, transformation, and output. Focused on API design and type safety, the work established a strongly-typed API surface that improves maintainability and onboarding for downstream integrations. In addition, implemented a feature enabling explicit frame-count control for spritesheets by adding an imageCount property to media transformation output options, enhancing processing capabilities and rendering workflows. The approach aligned new interfaces with existing Workerd patterns, ensuring consistency and ease of adoption. All contributions were delivered using TypeScript, with an emphasis on robust type definitions and API clarity.