Shane Handley developed security-focused document sandboxing controls in the servo/servo repository, implementing active sandboxing flags for new documents based on Content Security Policy settings. Using Rust and JavaScript, Shane introduced management methods and comprehensive tests to validate the new behavior, directly addressing security risks related to autoplay and form submissions. To improve reliability, Shane also removed a consistently failing web platform test that conflicted with sandboxing requirements, reducing CI noise and stabilizing the test suite. This work demonstrated a thoughtful approach to backend and web development, balancing feature delivery with test hygiene and aligning with business goals around safer content handling.