MxBuild & Custom Widgets

As far as I understand, when developing React custom widgets it is standard practice to commit the result .mpk file.  We deploy our app in docker and if we are not careful, we can end up with development widget builds rather than release builds in the repository.  I was working to customise our docker build so that it builds the widgets in release, overwriting whatever might be in the repo, when I saw that the output of MxBuild contains a couple of lines about ‘Creating custom widgets bundles’.   Am I right in thinking that MxBuild does *not* already create release builds of the .mpk files and instead uses what is already in the repository?  (If it does do this then my work is not necessary….)  
1 answers

AFAIK mxbuild is a command line tool that builds non versioned versions of you project.

This is the same option available in the modeler and this uses the local data, not the repository data.