I would just go: “I help create bank applications that work the best they can.”
I don’t see myself as a bystander who just reports on stuff or looks for bugs. My mission is to be there and help plan and predict what can go wrong and which paths to take. Also to support the core Dev people produce the code as fast as possible with as high quality as possible.
I am often part of a discussion which route to take, technologies to implement, how to fix something or just about how it should look. When I want to, I fix/implement stuff myself.