BackendTable-stakesLegacy
SOAP / XML Web Services
Also written as SOAP, WSDL, XML Web Services
The older, stricter, XML-based way for systems to talk to each other, which REST largely replaced. Still common in banking, insurance, telecoms, government and SAP integrations.
Think of it like
Formal registered post with forms in triplicate, compared with REST's quick email.
Junior or senior?
Expected in enterprise integration and legacy modernisation roles. Seen alone on a resume for a modern product role, it suggests the stack is dated.
Ask them
“Which systems still needed SOAP, and did you ever move one of those integrations to REST?”