diff --git a/src/Aggreact/Comments/Types.hs b/src/Aggreact/Comments/Types.hs
index 851f9ef..b3062b6 100644
--- a/src/Aggreact/Comments/Types.hs
+++ b/src/Aggreact/Comments/Types.hs
@@ -52,7 +52,7 @@ where
 
 import           Protolude
 
-import           Aggreact.Users                   (User, UserId (..), BUserId)
+import           Aggreact.Users                   (User, UserId (..), BUserT, BUserId)
 
 import qualified Control.Exception                as Ex
 import           Data.Aeson                       (FromJSON (..), ToJSON (..),
@@ -144,7 +144,7 @@ bCommentToComment bc =
    { parent = _parent bc
    , slug = _slug bc
    , content = _content bc
-   , userid = MUserId (_userid bc)
+   , userid = _userid bc
    })
   (DefaultMetas
    { updated = _updated bc
@@ -155,10 +155,10 @@ data BCommentT f =
   { _parent  :: Beam.Columnar f ParentId -- ^ UUID
   , _slug    :: Beam.Columnar f Slug     -- ^ Text (URL)
   , _content :: Beam.Columnar f Content  -- ^ Text
-  , _userid  :: Beam.Columnar (Beam.Nullable f) BUserId -- ^ UUID
   , _created :: Beam.Columnar f UTCTime
   , _updated :: Beam.Columnar f (Maybe UTCTime)
   , _id      :: Beam.Columnar f Id
+  , _userid  :: Beam.PrimaryKey BUserT (Beam.Nullable f) -- ^ UUID
   } deriving (Generic)
 type BComment = BCommentT Identity
 type BCommentId = Beam.PrimaryKey BCommentT Identity
diff --git a/src/Aggreact/Users/Types.hs b/src/Aggreact/Users/Types.hs
index 5027f84..93ac7b0 100644
--- a/src/Aggreact/Users/Types.hs
+++ b/src/Aggreact/Users/Types.hs
@@ -92,10 +92,13 @@ data BUserT f =
   } deriving (Generic)
 type BUser = BUserT Identity
 type BUserId = Beam.PrimaryKey BUserT Identity
+type BMUserId = Beam.PrimaryKey BUserT (Beam.Nullable Identity)
 deriving instance Show BUser
 deriving instance Eq BUser
 deriving instance Show BUserId
 deriving instance Eq BUserId
+deriving instance Show BMUserId
+deriving instance Eq BMUserId
 instance Beam.Beamable BUserT
 instance Beam.Table BUserT where
   data PrimaryKey BUserT f =