anchor.diff:  
             %% What member type are we checking for?  This will always be an actor or
             %% a group
  -          member_type :: entity_type(),
  +          member_type :: auth_type(),
   
             %% What's the ID of the member
  -          member_id :: binary(),
  +          member_id :: auth_id(),
   
             %% Who's asking?
  -          requestor_id :: binary(),
  +          requestor_id :: auth_id(),
   
             %% Which module is handling this request?
             module :: atom()
  
positive.code: 
            %% Who are we working with?  This is the object in question, i.e., for
            %% /<type>/<id> this is <id>
            authz_id :: binary(),
  
            %% What kind of resource are we talking about here?
            request_type :: entity_type(),
  
            %% What is the ACL on the resource?
            acl :: term(),
  
negative.code: %% a function declaration so breaks all of our behavior callbacks.
  -include_lib("webmachine/include/wm_reqdata.hrl").
  -include_lib("mixer/include/mixer.hrl").
  -include("heimdall.hrl").
  
  -type permission() :: create | read | update | delete | grant.
  
  %% Share resource state shared by all heimdall resource modules
  %%
  