How do large agile organizations automate SIT?

I’m looking to have a conversation about how larger orgs are solving for Systems Integration testing in an automated fashion. We are a large organization with integrated systems ranging from legacy applications built on iSeries to newer applications born in the cloud (and everything in between). Dev teams are largely independent in terms of work process (e.g. agile methodology, test frameworks, delivery cadence, etc.) Some teams are CD, delivering to production multiple times a day/week where some deliver once a month. Most of our teams have automation frameworks which cover Functional and Integration tests. We are fairly consistent on using Ruby to build frameworks but there are teams using other tools. While teams generally test in a common integration environment, there is no overall Systems Integration Testing done at an enterprise/business process level. We are looking to mature that process but I’m wondering how others have approached the problem. What I really don’t want to do is create a new team of people who solely build and run SIT tests. How do organizations with similar challenges approach SIT in an automated fashion?

Our constraints/challenges:
-No common delivery cycle
-No common codebase
-Mix of legacy and newer technologies
-No common tool set/framework

This is an interesting topic and i’m thinking about the same thing here. We have similar constraints to yourself and I am reluctant to have a separate team looking after these SIT’s or platform level testing (it’s not very Agile, I don’t want the overhead of maintaining a separate framework outside the Agile teams.).
One thing I was thinking of trying out is CDC (Consumer Driver Contracts) which gives some level of System testing and which can be done by people on the different Agile teams (it’s for the most part application language agnostic).

Thanks for the reply! CDC is something for me to dive into and see how that may work. Have you implemented this approach anywhere in your organization? If so, I’d love to hear about your experience, lessons learned, etc.

Not yet but it’s something I want to POC. It will involve getting buy in from the Agile teams. What I like about this approach is that it really encourages communication and collaboration, plus it fits nicely into build pipelines, Agile model.