If you are building a pipeline or tools to run on FireCloud, you may benefit from existing Docker images. For example, when you write the WDL for your tool, it could be easier to reference a Docker image that already contains Matlab or other dependencies.
You may have found the Broad Institute's public Docker Hub repository: broadinstitute. This repository includes a Docker image for the Firecloud-CLI that enables you to upload tools to FireCloud. However, this repo is not particularly helpful if you are building tools.
Eventually, FireCloud may support a Docker Hub repository with best practice images for tool developers. In the meantime, you can check out the Broad GDAC repository: broadgdac. Here you can find Docker images for R, Matlab, Nozzle, and other GDAC tools (e.g., GISTIC2.0) that could integrate with your pipeline.