Since Mikrotik RouterOS is based on Linux it was possible to start supporting Containers. This support is a fact since RouterOS v.7.5.
They support multiple types and the one that is most anticipated is Docker Containers.
This opens up for a whole lot of new possibilities, like running PIHole or Unifi controller or some other usefull Docker image on your router itself.
There are some requirement: your router HW architecture must be one of the following:
You should also connect an external USB drive to your Mikrotik, unless your MT already has got a buildtin M2 disk or similar.
You start by simply downloading the extra package from the Mikrotik website.
You will need physical access to your device since one of the security measures is that you need to physically press the reset button on the device.
Before you do this, you should run the following command:
system device-mode update container=yes
This useful video from the Mikrotik company explains the details very well: