diff --git a/src/TypeChecker/TypeCheckerBidir.hs b/src/TypeChecker/TypeCheckerBidir.hs
index 1f16e11..60667c5 100644
--- a/src/TypeChecker/TypeCheckerBidir.hs
+++ b/src/TypeChecker/TypeCheckerBidir.hs
@@ -39,7 +39,6 @@ import qualified TypeChecker.TypeCheckerIr as T
 -- • Fix problems with types in Pattern/Branch in TypeCheckerIr
 -- • Use applyEnvExp consistently
 -- • Fix the different type getters functions (e.g. partitionType) functions
--- • Handle recursive functions. Maybe use a isRec : Bool variable.
 
 data EnvElem = EnvVar         LIdent Type -- ^ Term variable typing. x : A
              | EnvTVar        TVar        -- ^ Universal type variable. α
@@ -53,44 +52,43 @@ type Env = Seq EnvElem
 -- | Ordered context
 -- Γ ::= ・| Γ, α | Γ, ά | Γ, ▶ ά | Γ, x:A
 data Cxt = Cxt
-    { env        :: Env                                  -- ^ Local scope context  Γ
-    , sig        :: Map LIdent Type                      -- ^ Top-level signatures x : A
-    , binds      :: Map LIdent Exp                       -- ^ Top-level binds x : e
-    , next_tevar :: Int                                  -- ^ Counter to distinguish ά
-    , data_injs  :: Map UIdent Type                      -- ^ Data injections (constructors) K/inj : A
+    { env        :: Env             -- ^ Local scope context  Γ
+    , sig        :: Map LIdent Type -- ^ Top-level signatures x : A
+    , binds      :: Map LIdent Exp  -- ^ Top-level binds x : e
+    , next_tevar :: Int             -- ^ Counter to distinguish ά
+    , data_injs  :: Map UIdent Type -- ^ Data injections (constructors) K/inj : A
     } deriving (Show, Eq)
 
 newtype Tc a = Tc { runTc :: ExceptT String (State Cxt) a }
     deriving (Functor, Applicative, Monad, Alternative, MonadState Cxt, MonadError String)
 
-typecheck :: Program -> Err (T.Program' Type)
-typecheck (Program defs) = do
-    datatypes <- mapM typecheckDataType [ d | DData d <- defs ]
-
-
-    let initCxt = Cxt
-            { env          = mempty
-            , sig          = Map.fromList [ (name, t)
-                                          | DSig' name t <- defs
-                                          ]
-            , binds        = Map.fromList [ (name, foldr EAbs rhs vars)
-                                          | DBind' name vars rhs <- defs
-                                          ]
-            , next_tevar   = 0
-            , data_injs = Map.fromList [ (name, t)
-                                       | Data _ injs <- datatypes
-                                       , Inj name t <- injs
-                                       ]
+initCxt :: [Def] -> Cxt
+initCxt defs = Cxt
+            { env        = mempty
+            , sig        = Map.fromList [ (name, t)
+                                        | DSig' name t <- defs
+                                        ]
+            , binds      = Map.fromList [ (name, foldr EAbs rhs vars)
+                                        | DBind' name vars rhs <- defs
+                                        ]
+            , next_tevar = 0
+            , data_injs  = Map.fromList [ (name, t)
+                                        | DData (Data _ injs) <- defs
+                                        , Inj name t <- injs
+                                        ]
             }
 
-    binds' <- evalState (runExceptT (runTc $ mapM typecheckBind binds)) initCxt;
-    pure . T.Program $ map T.DData (coerceData datatypes) ++ map T.DBind binds'
-  where
-    binds = [ b | DBind b <- defs ]
-    -- TODO this should happen in typecheckDataType
-    coerceData = map (\(Data t injs) -> T.Data t $ map
-                     (\(Inj name typ) -> T.Inj (coerce name) typ) injs)
+typecheck :: Program -> Err (T.Program' Type)
+typecheck (Program defs) = do
+    dataTypes' <- mapM typecheckDataType [ d | DData d <- defs ]
+    binds' <- typecheckBinds (initCxt defs) [b | DBind b <- defs]
+    pure . T.Program $ map T.DData dataTypes' ++ map T.DBind binds'
 
+typecheckBinds :: Cxt -> [Bind] -> Err [T.Bind' Type]
+typecheckBinds cxt = flip evalState cxt
+                   . runExceptT
+                   . runTc
+                   . mapM typecheckBind
 
 typecheckBind :: Bind -> Tc (T.Bind' Type)
 typecheckBind (Bind name vars rhs) = do
@@ -105,7 +103,7 @@ typecheckBind (Bind name vars rhs) = do
             pure (T.Bind (coerce name, t') [] (e', t'))
     env <- gets env
     unless (isComplete env) err
-    insertSig (coerce name) typ -- HERE
+    insertSig (coerce name) typ
     putEnv Empty
     pure bind'
   where
@@ -114,11 +112,11 @@ typecheckBind (Bind name vars rhs) = do
         , "Did you forget to add type annotation to a polymorphic function?"
         ]
 
-typecheckDataType :: Data -> Err Data
+typecheckDataType :: Data -> Err (T.Data' Type)
 typecheckDataType (Data typ injs) = do
     (name, tvars) <- go [] typ
     injs' <- mapM (\i -> typecheckInj i name tvars) injs
-    pure (Data typ injs')
+    pure (T.Data typ injs')
   where
     go tvars = \case
       TAll tvar t -> go (tvar:tvars) t
@@ -128,7 +126,7 @@ typecheckDataType (Data typ injs) = do
           -> pure (name, tvars')
       _ -> throwError $ unwords ["Bad data type definition: ", ppT typ]
 
-typecheckInj :: Inj -> UIdent -> [TVar] -> Err Inj
+typecheckInj :: Inj -> UIdent -> [TVar] -> Err (T.Inj' Type)
 typecheckInj (Inj inj_name inj_typ) name tvars
     | not $ boundTVars tvars inj_typ
     = throwError "Unbound type variables"
@@ -136,7 +134,7 @@ typecheckInj (Inj inj_name inj_typ) name tvars
     , name'  == name
     , Right tvars' <- mapM toTVar typs
     , all (`elem` tvars) tvars'
-    = pure (Inj inj_name $ foldr TAll inj_typ tvars')
+    = pure $ T.Inj (coerce inj_name) (foldr TAll inj_typ tvars')
     | otherwise
     = throwError $ unwords
         ["Bad type constructor: ", show name
@@ -470,7 +468,6 @@ infer = \case
         e2'' <- applyEnvExpT e2'
         pure (T.EAdd e1'' e2'', int)
 
-
     --                  Θ ⊢ Π ∷ A ↓ C ⊣ Δ
     --  Γ ⊢ e ↓ A ⊣ Θ   Δ ⊢ Π covers [Δ]A TODO
     --  ---------------------------------------
@@ -612,7 +609,7 @@ checkPattern patt t_patt = case patt of
                 -- insertEnv (EnvTEVar tevar)
                 pure $ substitute tvar tevar t
               where
-                TAll tvar _ = fa dummy
+                TAll tvar _ = fa int
 
             getParams = \case
                 TAll _ t -> getParams t
@@ -856,8 +853,6 @@ modifyEnv f =
 pattern DBind' name vars exp = DBind (Bind name vars exp)
 pattern DSig' name typ = DSig (Sig name typ)
 
-dummy = TLit "Int"
-
 ---------------------------------------------------------------------------
 -- * Debug
 ---------------------------------------------------------------------------