Worked on the storybookjs/storybook repository to address module resolution and runtime errors related to ECMAScript Modules. Focused on improving ESM compatibility by enforcing explicit .js extensions in import statements, aligning the codebase with modern ESM requirements. This targeted fix reduced breakages for users migrating to ESM and enhanced the reliability of module resolution across different builds and runtimes. Demonstrated proficiency in JavaScript and TypeScript, applying knowledge of Node and front end development to incrementally improve backend stability. The work contributed to smoother user experiences and more robust Storybook distributions in ESM environments, with measurable impact on downstream consumers.