The current Azure IoT Edge public preview uses Docker to deploy logic from the cloud into local gateways. It's currently featuring:
C# modules written in .Net standard
Azure Function built on your machine
Azure Stream Analytics jobs built and deployed in the cloud
Azure Machine Learning
We can expect Microsoft will support other types of modules soon as they have proven with other recent projects. An Azure Cognitive Services module is a good example, it's put in every IoT Edge presentation.
The IoT Edge portal makes it possible to deploy modules which are available in private or public image repositories.
Could it be possible to build and deploy images to the gateway which are not specifically designed for IoT Edge?
It turns out, it is possible.
Let's deploy a NodeJS server which serves SocketIO.