...In application development, it provides an O/R mapping system and template systems on an MVC architecture, aims to achieve high productivity through the policy of convention over configuration. TreeFrog Framework is cross-platform. It runs on Windows, of course, but also on UNIX-like Operating Systems, macOS, and Linux. Using Windows open-source coding, it is possible to support Linux. Web applications that run on multiple platforms are also possible, simply by recompiling the source code. TreeFrog Framework is open-source software, under the new BSD license (3-clause BSD License).