Worked on the nuxt/nuxt repository to improve runtime configuration reliability by addressing a bug in environment variable expansion. Focused on aligning the regex used for parsing environment variables with Nitro’s expected format, ensuring accurate substitution within configuration values. The solution involved optimizing regular expressions and enhancing the runtime configuration module, with comprehensive tests written in JavaScript and TypeScript to validate behavior across multiple scenarios. This work reduced configuration-related errors and improved Nitro compatibility, resulting in more dependable deployments and streamlined CI and development workflows. Demonstrated skills in configuration management, full stack development, Node.js, and test-driven development practices.