Worked on the leptos-rs/cargo-leptos repository to enhance backend build reliability using Rust. Focused on hardening the build and parsing pipeline, introducing a fault-tolerant CSS parsing mechanism that preserves the original input when parsing fails, thereby preventing cascading errors in the CSS processing workflow. Additionally, improved the wasm-bindgen build watch loop by enabling it to handle interrupts gracefully, allowing the process to enter a stopped state rather than terminating unexpectedly. These backend improvements reduced build downtime and improved CI reliability, supporting a smoother development experience. The work demonstrated attention to robust error handling and process resilience in Rust environments.