Here is the sharing settings for account/contract: 
Our experience users (community) have to access (read/write) the contract records under the account their contact is linked to but only those ones. The crud on the user's profile is read/create/edit enabled. Changing the sharing settings to public read/write or updating the crud to modify all won't fit here since they should access only the contracts under their company. I wanted to update the contract__Share via apex but since contract__Share doesn't exist, it's not possible... how can this be done?
Thanks!

