The TeamCity API allows developers to make HTTP requests to the TeamCity server and get a response. The API is REST-based and is available as an open-source plugin. This API can be authenticated using basic HTTP authentication.
Version 6.5 of the API provides developers with an unlimited number of users, the ability to use any authentication scheme, and the ability to use adjustable per-project permissions. Essentially, all features of the Enterprise Edition are now available in Professional Edition. However, the maximum number of build configurations in Professional Edition is still 20.
TeamCity is a Java-based continuous integration and build management server from JetBrains.