natural-transformation / korolev   1.17.2

Apache License 2.0 GitHub

Single Page Applications running on the server side

Scala versions: 3.x


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Not long ago we have entered the era of single-page applications. Some people say that we no longer need a server. They say that JavaScript applications can connect to DBMS directly. Fat clients. We disagree with this. This project is an attempt to solve the problems of modern fat web.

Korolev runs a single-page application on the server side, keeping in the browser only a bridge to receive commands and send events. The page loads instantly and works fast, because it does a minimal amount of computation. It's important that Korolev provides a unified environment for full stack development. Client and server are now combined into a single app without any REST protocol or something else in the middle.


  • Lightning-fast page loading speed (~6kB of uncompressed JS)
  • Comparable to static HTML client-side RAM consumption
  • Indexable pages out of the box
  • Routing out of the box
  • Build extremely large app without increasing size of the page
  • No need to make CRUD REST service
  • Connect to infrastructure (DBMS, Message queue) directly from application