Our partners are also large companies with automated administration, with several programs running on several machines. We have no interest in their architecture and the technology they use, but we want to integrate their operations. We want to serve them in a way that doesn't require any human interaction for the administration to order goods on either of our sides. To do so, a web service interface is provided that can be utilized no matter what IT infrastructure they use.
On our side, as we imagine the example, we recently replaced our monolithic application with microservices architecture, and though there are still some SOAP-based solutions in the system, most of the backend modules communicate using HTTPS ...