18.45The mini-project you should be able to build from memory

If you have time before the interview, practice exactly this one application:

POST /customers

Input:

{
  "customerId": "C001",
  "companyName": "Acme",
  "phone": "3055551234",
  "contacts": [
    {
      "contactId": "P001",
      "firstName": "John",
      "lastName": "Smith"
    }
  ]
}

Flow:

HTTP Listener
↓
Validate
↓
Save original request
↓
Transform Account
↓
Salesforce Upsert Account
↓
Save Account ID
↓
Transform Contacts
↓
Salesforce Upsert Contacts
↓
Response

Add:

error handler
MUnit happy path
MUnit Salesforce error

If you can explain/build that, most of the interview topics emerge naturally.