I have an existing scheduling code-base written entirely in JavaScript. At the moment its only fully working feature is the user-notification system, yet the app is already showing performance bottlenecks that slow page loads and make real-time updates feel sluggish. What I need first is a thorough cleanup and refactor that targets performance: untangle duplicated logic, remove dead code, split oversized functions, and trim the bundle so it ships fast. While you work, please leave the code more readable and well-documented so future contributors can follow along without guesswork. Your primary deliverable will be a redeployed build that runs noticeably faster on both desktop and mobile. If you spot bugs on the way, squash them—clean tests must pass before hand-over. After that, we can discuss expanding the feature set to include options such as appointment booking or full calendar integration, but for now the focus is a lean, efficient core built on modern JavaScript best practices (ES6+, modular structure, linting, webpack or Vite, etc.). To accept the job, let me know: • the performance profiling tools you prefer (e.g., Lighthouse, Chrome DevTools, WebPageTest) • how you plan to measure before/after speed gains • an estimated timeline to deliver the refactored code and deployment instructions Once the optimized build is in place, I’ll handle live testing and sign off. I’m ready to start as soon as you are.