diff --git a/registry.cabal b/registry.cabal
--- a/registry.cabal
+++ b/registry.cabal
@@ -4,10 +4,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: cbbe4d160e44dac16179f493abbb7d0c83446f5ccd2bfe031502caf6091dd958
+-- hash: e92b2f66ceff7a38e91de8e96c196577dec1046ec2f078503644b8bcb01419cb
 
 name:           registry
-version:        0.1.3.5
+version:        0.1.3.6
 synopsis:       data structure for assembling components
 description:    This library provides a "Registry" which is a data structure containing a list of functions and values representing dependencies in a directed acyclic graph. A `make` function can then be used to create a value of a specific type out of the registry.
                 You can start with the [README](https://github.com/etorreborre/registry/blob/master/README.md) for a full description of the library.
diff --git a/src/Data/Registry/TH.hs b/src/Data/Registry/TH.hs
--- a/src/Data/Registry/TH.hs
+++ b/src/Data/Registry/TH.hs
@@ -189,11 +189,21 @@
 typesOf (AppT (AppT PromotedConsT t) rest) = (typeName t, t) : typesOf rest
 typesOf _ = []
 
--- | Extract the name of a type, prettified up to 2 type constructors
+-- | Extract the name of a type
+--   There is a bit of massaging for tuple and arrow types for better display
 typeName :: Type -> String
 typeName (ConT n) = nameBase n
-typeName (AppT (ConT t1) (ConT t2)) = nameBase t1 <> "[" <> nameBase t2 <> "]"
-typeName (AppT (AppT (ConT t1) (ConT t2)) (ConT t3)) = nameBase t1 <> "[" <> nameBase t2 <> "[" <> nameBase t3 <> "]" <> "]"
+typeName (AppT (AppT (TupleT 2) t1) t2) = "(" <> typeName t1 <> "," <> typeName t2 <> ")"
+typeName (AppT (AppT (AppT (TupleT 3) t1) t2) t3) = "(" <> typeName t1 <> "," <> typeName t2 <> "," <> typeName t3 <> ")"
+typeName (AppT (AppT (AppT (AppT (TupleT 4) t1) t2) t3) t4) = "(" <> typeName t1 <> "," <> typeName t2 <> "," <> typeName t3 <> "," <> typeName t4 <> ")"
+typeName (AppT (TupleT i) t) = "Tuple" <> show i <> "(" <> typeName t <> ")"
+typeName (AppT (AppT ArrowT t1) t2) = typeName t1 <> " -> " <> typeName t2
+typeName (AppT (AppT (AppT ArrowT t1) t2) t3) = typeName t1 <> " -> " <> typeName t2 <> " -> " <> typeName t3
+typeName (AppT (AppT (AppT (AppT ArrowT t1) t2) t3) t4) = typeName t1 <> " -> " <> typeName t2 <> " -> " <> typeName t3 <> " -> " <> typeName t4
+typeName (AppT ArrowT t) = typeName t <> " -> "
+
+typeName (AppT ListT t) = "[" <> typeName t <> "]"
+typeName (AppT t1 t2) = typeName t1 <> "(" <> typeName t2 <> ")"
 typeName t = show t
 
 -- | Return a deduplicated list of types from a list of types
diff --git a/test/Test/Data/Registry/SimpleExamples.hs b/test/Test/Data/Registry/SimpleExamples.hs
--- a/test/Test/Data/Registry/SimpleExamples.hs
+++ b/test/Test/Data/Registry/SimpleExamples.hs
@@ -106,3 +106,36 @@
 -- | This version compiles but throws an exception at runtime
 dangerous :: Text1
 dangerous = makeUnsafe @Text1 registry3
+
+-- | Example with an optional configuration
+--   The ProductionComponent will only be used if the ServiceConfig says we are in production
+newtype ProductionComponent = ProductionComponent { doItInProduction :: IO () }
+data ProductionConfig = ProductionConfig deriving (Eq, Show)
+
+newtype Service = Service { service :: IO () }
+data ServiceConfig = InProd | InDev deriving (Eq, Show)
+
+-- | Production component definition
+
+-- Normal constructor
+newProductionComponent :: ProductionConfig -> Logging -> ProductionComponent
+newProductionComponent _ _ = ProductionComponent (pure ())
+
+-- Constructor which returns a "builder function", only used if a `ProductionConfig` is available
+newProductionComponentBuilder :: Logging -> Tag "builder" (ProductionConfig -> ProductionComponent)
+newProductionComponentBuilder = Tag . flip newProductionComponent
+
+-- | Service component definition
+--   It uses a builder for the ProductionComponent and only uses it in production
+newService :: ServiceConfig -> Tag "builder" (ProductionConfig -> ProductionComponent) -> Service
+newService InDev _ = Service { service = print ("dev" :: Text) }
+newService InProd f = Service { service = doItInProduction ((unTag f) ProductionConfig)  }
+
+registryWithOptionalComponents =
+     val InDev
+  +: fun newService
+  +: fun newProductionComponentBuilder
+  +: fun logging
+  +: end
+
+makeService = make @Service registryWithOptionalComponents