Selected intern's day-to-day responsibilities include:

1. Developing user-facing applications using Vue.js
2. Building modular and reusable components and libraries
3. Optimizing your application for performance
4. Implementing automated testing integrated into development and maintenance workflows
5. Staying up-to-date with all recent developments in the JavaScript and Vue.js space
6. Keeping an eye on security updates and issues found with Vue.js and all project dependencies
7. Proposing any upgrades and updates necessary for keeping up with modern security and development best practices

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