I can understand that concepts like flatMap, merge, reduce and zip can be intimidating at first. It would help to explain what they are and how they work with smaller examples outside of project code base.<p><a href="https:&#x2F;&#x2F;jsbin.com&#x2F;bemasodemi&#x2F;edit?js,console" rel="nofollow">https:&#x2F;&#x2F;jsbin.com&#x2F;bemasodemi&#x2F;edit?js,console</a>