Sorry to say, but this was the completely wrong approach and I’m amazed the business let you do it.

Some poor bastard is going to have to undo all your mess down the road, I hope you buy them a beer if they ever track you down. I mean, at what point do you make the call that writing your own in-house copy of _DOCKER_ is a smart move? Let alone Jenkins.. The ‘magic’ abilities you describe this platform as having are utterly standard features and are yours as soon as you install e.g gitlab...

Of course, you actually have to spend some time and learn them and how to use them properly, but that time is VASTLY less than learning how to implement them badly and minuscule compared to the amount of time it’s going to take to migrate off your in-house pile..