transparent concurrency for maximal
http service scalability

Comsat is a set of open source libraries that integrate Quasar with various Web or enterprise technologies (like HTTP services and database access). With Comsat, you can write web applications that are scalable and performant while, at the same time, are simple to code and maintain. You will enjoy the scalability of asynchronous services with no need to change your simple sequential code.


Standard APIs

Comsat is not a web framework. It provides implementations to standard APIs like Servlets, JAX-RS and JDBC so that your code changes little, if at all. It also provides an optional API that lets you use a natural actor model for web service programming.


Scalable Web Applications

Comsat lets your application enjoy the scalability of asynchronous web-frameworks, serving many thousands of concurrent long-lived connections, or issuing hundreds of web-service calls for each request, all while maintaining the simple “thread per request” model. Comsat’s increased scalability allows you to reduce the number of your web and application servers.


  • High concurrency – one fiber per request
  • Not a framework, but a set of standard APIs implementations
  • Optional actor model for simple implementation of interactive web
    applications (including WebSockets and SSE), with hot code swapping
  • Supports Tomcat, Jetty, and other web containers
  • JAX-RS RESTful services
  • Supports JDBC, file IO, HTTP client



Follow Comsat
on GitHub



Tutorial: Getting started with Comsat/Dropwizard and Comsat/Tomcat