Hello,
Thank you for your job posting. I can help you to modify the existing multiplayer game.
I'm technical and proficient in HTML5, CSS, Javascript and Node.js/Express JS for a portal website development.
In back-end development, I developed several real time servers using Node.js/Express JS and Socket.io.
I can help you to modify the existing game so I will make the functionality for the player to receive the possibility to collect starts.
As a 5 yrs experience with software development, work with medium and big companies in russia and satisfy client's requirements.
Through reading your description, my experience will help you and your project.
If you are interest, Please let me know and discuss your project in detail,
Best,
Okcana D.