what do contract-first and contract-last mean?

Question

I am doing some research on web services. I have not written any web service but I am doing a small write up on them.

During my research I\'ve come across terms

Answer 1

Contract-first means you design the way your services are going to communicate with each other before you design the services themselves.

Contract-last is the other way around – you design how your service is going to work, then make one or more methods available as the interface for other services.