You are in development mode when you start a MIRO app from GAMS Studio (or via the command line with the environment variable MIRO_DEV_MODE set to true). Every time you launch MIRO in development mode, your app resources (configuration, README file, data files etc.) are loaded and validated, so your application is always in sync with your current GAMS source. Once you want to share your application with other people you can deploy it. Deployed apps work with a compiled version of your resources, so they tend to launch faster. However, this also means that you can no longer change your app without deploying a new version.