We have automated our nightly build to upload to Steam.
This build is available to everyone, but it's slightly hidden away by default.
To access it, right-click Satellite Reign in your Steam library, select properties, and there should be a 'Betas' tab to the far right. Select this tab, and a drop-down menu will be available where you can select 'nightly.'
Be aware that this build will always contains work-in-progress changes. For example, right now, it contains a new metallic shader we are working on that is making some objects overly bright until they are setup properly.
In general, the nightly, while having latest bug-fixes over the default build, will also have new bugs or half-implemented features (and may sometimes have totally game-breaking bugs), so only grab this if you want to be on the cutting-edge and help us by finding new issues in the build.
Mike.