CosmicTunes

Chris's Spotify Constellation
Steven's Spotify Constellation

Inspiration

We wanted to make music more social and fun. Spotify shows us our top artists individually, but there isn’t an easy way to see how your tastes connect with others. The idea of turning playlists into constellations inspired us to create CosmicTunes — a space-themed way to visualize and share music overlaps.

What it does

CosmicTunes connects to your Spotify account, pulls your top artists, and maps them into a “cosmic room” that you can share with friends. When multiple people join a room, the app highlights overlaps, unique artists, and collective trends — letting you discover both common ground and new music recommendations interactively.

How we built it

We used Next.js for the frontend, Vercel for deployment, and Upstash Redis to store group sessions. Spotify’s Web API powers the retrieval of user listening data. We designed the flow so that each user has a persistent session, and friends can connect in real time by entering a shared room code.

Challenges we ran into

We ran into challenges such as managing Spotify authentication and refreshing tokens. We also had to solve how to persist user data temporarily while respecting privacy, as well as making sure group sessions didn’t overwrite each other. Finally, we had to develop and improve several design iterations to land on a design that shared artist data in a way that felt both intuitive and visually engaging

Accomplishments that we're proud of

We’re proud that CosmicTunes actually works end-to-end: from logging into Spotify, pulling top artists, and displaying overlaps across multiple users in real-time. We also love that the theme feels cohesive — turning music data into constellations makes the experience both functional and fun.

What we learned

We learned a lot about handling third-party APIs securely, especially around access tokens. We also got more hands-on experience with Redis as a lightweight storage solution for real-time apps. Beyond the technical side, we learned how important it is to balance visuals and usability when building something meant to be social.

What's next for CosmicTunes

We want to expand CosmicTunes with features like collaborative playlists based on group overlaps, integration with more streaming platforms, and better visualization of genre clusters. We still need to further develop group sessions so that they become functional without error. In the future, we’d also like to make it possible for groups to “compare universes” over time — turning Cosmic Tunes into an ongoing way to explore evolving music tastes with friends.