Zuul VS Ocelot

What's important is that Zuul gates your codebase, whereas other tools sometimes let faulty commits go through. Unfortunately there's a bit of a name collision with Netflix Zuul gateway service, but that's awesome F/OSS for another day.

Automatic load balancing — You might have used Netflix Zuul for this.

Check this one - https://github.com/Netflix/zuul

Sounds like you need some kind of ETL. The only dotnet library I know, which supports request aggregation, is Ocelot (https://github.com/ThreeMammals/Ocelot). But I doubt it is the only one out there.

They seems to recommend https://github.com/ThreeMammals/Ocelot

Ocelot Github Nuget: Install-Package Ocelot -Version 17.0.0

Ok, now that you created you Web API, it's time to work on your API Gateway. Start by adding the Ocelot package to your Gateway project:

Discovered Ocelot and it looks like a good place to start, so you have any thoughts on that?

I'd look for an open-source gateway using the programming language that you're familiar with. I was working multiple times with the custom API GW (including building my own for fun), and if you're familiar e.g. with C# take a look at this one https://github.com/ThreeMammals/Ocelot or even better https://github.com/microsoft/reverse-proxy If you need to build something really custom, there's a small chance that you will find a plug & play solution.

Lol, i guess your answer explains a lot about relevant knowledge into web architecture

Eg. Ocelot - https://github.com/ThreeMammals/Ocelot