JavaScript is coded as an interpreted language. This means that it is not compiled in advance like RPG, C++, or Java. The source code file and the executable file are one and the same. 

Whenever Node.js modules are used, however, Node automatically caches them for performance. When a module is cached, it doesn't have to be read from disk again and reinterpreted.

With traditional Node.js applications, cached modules are not reloaded until the node process is restarted. This means a server instance would have to be ended and started up again in order to incorporate changes to your applications.

To avoid downtime, Profound.js incorporates hot module reloading, a feature that invalidates the module cache immediately after a Profound.js module is modified. With this, you can deploy application changes instantly without having to restart Profound.js. Hot module reloading is enabled by default. To disable this feature, update the hotReloading flag in the Profound.js Configuration File.