Worked on the swc-project/swc repository to improve the accuracy of TypeScript declaration file emission, focusing on aligning generated .d.ts files with the TypeScript compiler’s output. Addressed issues by stripping definite assignment assertions from class members and removing default binding expressions from parameter binding patterns, which enhanced the reliability of downstream type-checking and improved compatibility with TypeScript tooling. Utilized skills in compiler development, Rust, and TypeScript to implement these changes, resulting in reduced boilerplate for library consumers and more stable typings. The work targeted a specific bug, demonstrating attention to detail and a strong understanding of TypeScript’s declaration emit process.