Does a deleted user's API key remain functional?

Question 

If I delete a user, can I still use their API keys in an integration configuration?

Environment

All versions of xMatters

Answer

When you delete a user from xMatters, their API keys are also deleted. If you use the deleted API keys in an integration, xMatters returns an error indicating the keys are no longer valid.

It's a good practice to create separate, integration-specific users when configuring an integration, although each user will occupy a user license. (You can also create a single integration user and have that account authenticate multiple integrations.)