Single Page Apps and DevOps Pipeline?
When starting from scratch first build a set of scripts (bash and golang) which start with a git pull to get the fresh code for a given branch then the script issues all the command line steps you can do yourself to compile the code into executable bundles.  This includes issuing Docker commands to cut fresh docker images for the various microservices.  Then a script launches all the various Docker containers.  Now the app can get fresh code pushed to domains where people can login and use the app from their client (mobile or browser) whenever a developer requests a domain needs a refresh.

The next step for us was to setup a github webhook server on each server for each domain which subscribes to all git push performed by our developers.  If a given git push matches the github code branch a domain is running the webhook would trigger launch of the above script to compile then deploy the app

All of above is just automation to replace what someone was originally manually issuing themselves at the command line.  As need appeared a new step was issued manually until it got crafted into above tooling.