For App Store Connect automation including automatic app uploads, we need an API key granting admin access to your App Store Connect API: https://developer.apple.com/app-store-connect/api/

To generate the API key, sign in to App Store Connect as an Admin user and navigate to Users and Access. Then select Keys in the secondary menu. If you do not see the Keys option in the secondary menu you may not have Admin access to that account.

 

Select the option to add a new API key and provide a useful name, granting Admin access.

Generate the new API Key and download the P8 file, store this in a secure location and share alongside the Issuer ID and the Key ID (found on the same page) with Pugpig using an encrypted service such as Keybase.