Extensibility API for C# Developers

Last modified: September 25, 2025

Introduction

Extensions can be written in C#, described here, or using a web API (for more information about the Web API, see Extensibility API for Web Developers).

To add a custom UI to Studio Pro, you can use web technology. Your web-based UI will be rendered in Studio Pro through a hosted web view, and the API provides communication between your UI and the C# extension logic.

Prerequisites

To use the C# API, you must have:

  • A basic understanding of the Mendix platform
  • Some understanding of the Mendix Model
  • Come C# development experience

Extensions are developed using C# and compiled into a .dll assembly file.

Getting Started

For detailed information on how to get started with extensions, see Get Started with the Extensibility API.

You can also review some examples and API reference documentation.

How-tos

Here is a list of how-tos for you to begin with:

Advanced APIs

Below are APIs for advanced users:

Reference Guide

Review the following reference guides to explore additional Extensibility API topics: