Creating Modules

Last modified: September 29, 2025

Introduction

Follow these guidelines when developing modules for the Marketplace:

  • Create a folder named USE_ME, and add the microflows and pages that are relevant for the user.

  • Create an empty folder with the version number as its name, which will appear in Studio Pro's App Explorer.

  • For Java dependencies, follow these guidelines:

    • In versions Mendix 10.3.0 and above, use managed dependencies where possible.

    • In versions below 10.3, ensure that Java dependencies are put in the userlib folder. You should also put any unmanaged dependencies, that is, non-publicly-available .jar files, in the userlib folder.

      • When putting .jar files in the userlib folder, make sure that the name includes a version number (for example, org.apache.commons.io-2.3.0.jar), and that it is accompanied by a blank {jarfile-including-version}.{module_name}.RequiredLib file. This is so users know where the .jar files come from. For example, for the MyModule component, this would be org.apache.commons.io-2.3.0.jar.MyModule.RequiredLib.

  • Verify that the module's Java actions compile correctly. The easiest way to check is to create a deployment package, as it will clean the deployment folder and rebuild the app. For more information, see Environments.

  • Reduce the use of layouts and use snippets instead. This results in fewer module dependencies, and reduces the number of potential errors, such as missing layouts.

  • Implement user roles and security.

  • Creating a new release or module export only while the security level of the app containing the module is set to Production.

  • The status must be Complete for the following access: page, microflow, OData, entity, and dataset.

  • For example pages and microflows to be copied to another module, select the Exclude from project option for the document. This encourages duplication and reduces dependency errors.

  • Do not rename entities and attributes when creating new versions, as data in these entities will get lost. Replacing an existing module is based on the entity names.

  • The module must include the English language.