Is it possible to populate custom fields for users?

Yes, you should be able to write whatever values you want to custom fields or custom user roles via the API. 

• Custom fields: https://api2-us-west-2.insided.com/docs/user/#tag/User/operation/UpdateProfileField
• Custom roles: 
  • https://api2-us-west-2.insided.com/docs/user/#tag/User/operation/addRole
  • https://api2-us-west-2.insided.com/docs/user/#tag/User/operation/bulkUserAddRole

(note US region links for all of those)

We do something similar with Salesforce, pushing their Account Type as a custom role. Zapier is the automation tool we use, but any RPA tool should allow you to automate this process. 

​@hilaryschuldt Hi! Yes, this is generally possible. I think this thread does a really good job of laying out the two main possibilities:

Essentially, you can either:

1. Do this at the time of sign in/registration using SSO. This post contains technical details on how to do that, but this flowchart gives you the gist of “fetching user profile data.”

2. 

   Automate this to happen independently of SSO using Gainsight’s API/an automation tool of your choice like Zapier or Workato. Essentially, you could configure something like user signs in → find customer’s point of contact in Salesforce (or elsewhere) → assign this piece of information to the user as a piece of information in their profile. This requires using a combination of webhooks, API endpoints, or potentially any out-of-the-box trigger/action events that Zapier provides (unfortunately, Workato doesn’t provide any for Gainsight CC). 

Oops! I took long enough to type that my page hadn’t refreshed with ​@DannyPancratz’s response. :) He’s a pro at these kinds of automations. 

Thank you to both of you, both answers are helpful!