I have been using this for several years now. Great stuff! :) The only part that was missing from this was something that can update your deployments on image build. That's when I built Keel https://github.com/keel-hq/keel.

Basically, I have one trigger to always build from master but the rest are triggered by tag, for example, "1.2.5" and it builds the same image, then Keel updates affected workloads. So far I have never had to pay for it, apparently managing to stay in the free tier :)

Works way faster than automated Docker cloud builds either.