Welcome to Sekai Wiki this site is the place where you can look and observe the data of the game Project Sekai: Colorful Stage feat. Hatsune Miku like cards, events, and so on.

The work is still in progress though but it will keep improving overtime.


If you're devs, you can contributing to this project on GitHub as well.


I would like to shout out to the team of Sekai Viewer for providing assets and data to make this site possible.

Techonology Stack

Core framework

This site is built with Next and deployed on Vercel to maximize the capabilities of Next itself

  • All of the data are static, so I use Static Generation to cooked all of the data on build time, so there will not be any waiting time for the data to process
  • Most of image assets are already served in WebP form CDN though, but file sizes can still be able to improve. So, thanks to the major update of Next 10 I am able to use Automatic Image Optimization to optimize and cache optimized image on-the-fly. (This will help to reduce CDN bandwidth as well because when image has been requested once, it will pull data from cache instead for the second time.)
  • (This is not included at this moment) This site is offline-ready, if your browser supports Service Worker

MediaSession API


If you've listen to music or watch music video once, you may noticed the media controller on the top of the browser (or in the notificaion). I nailed it with MediaSession API to send metadata to system and handle all of the events by myself.

Check out more if you want to use it here on web.dev blog