diff --git a/registry-hedgehog.cabal b/registry-hedgehog.cabal
--- a/registry-hedgehog.cabal
+++ b/registry-hedgehog.cabal
@@ -1,13 +1,13 @@
 cabal-version: 1.12
 
--- This file has been generated from package.yaml by hpack version 0.34.4.
+-- This file has been generated from package.yaml by hpack version 0.35.0.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 7d0b0684f2ba9eb6cb838ca63d1f08de7ee191046c523b7d0ede13b888d63a06
+-- hash: 6507ac5c7059bc022b2cad2faa557a32b1ed204586dcf512efe171e1e61d5a49
 
 name:           registry-hedgehog
-version:        0.7.0.5
+version:        0.7.1.0
 synopsis:       utilities to work with Hedgehog generators and `registry`
 description:    This library provides some functions to extract generators from a "Registry" and make stateful modifications of that Registry to precisely control the generation of data
 category:       Control
@@ -33,33 +33,17 @@
   hs-source-dirs:
       src
   default-extensions:
-      BangPatterns
       DefaultSignatures
-      EmptyCase
-      ExistentialQuantification
-      FlexibleContexts
-      FlexibleInstances
       FunctionalDependencies
       GADTs
-      GeneralizedNewtypeDeriving
-      InstanceSigs
-      KindSignatures
       LambdaCase
-      MultiParamTypeClasses
       MultiWayIf
-      NamedFieldPuns
       NoImplicitPrelude
       OverloadedStrings
       PatternSynonyms
-      Rank2Types
-      RankNTypes
-      ScopedTypeVariables
-      StandaloneDeriving
-      TupleSections
-      TypeApplications
+      StrictData
       TypeFamilies
       TypeFamilyDependencies
-      TypeOperators
   ghc-options: -Wall -Wcompat -Wincomplete-record-updates -fhide-source-paths -fprint-potential-instances -fno-warn-partial-type-signatures -optP-Wno-nonportable-include-path -Wincomplete-uni-patterns
   build-depends:
       base >=4.14 && <5
@@ -78,7 +62,7 @@
     , transformers >=0.5 && <2
     , universum ==1.*
     , unordered-containers >=0.1 && <1
-  default-language: Haskell2010
+  default-language: GHC2021
 
 test-suite spec
   type: exitcode-stdio-1.0
@@ -98,33 +82,17 @@
   hs-source-dirs:
       test
   default-extensions:
-      BangPatterns
       DefaultSignatures
-      EmptyCase
-      ExistentialQuantification
-      FlexibleContexts
-      FlexibleInstances
       FunctionalDependencies
       GADTs
-      GeneralizedNewtypeDeriving
-      InstanceSigs
-      KindSignatures
       LambdaCase
-      MultiParamTypeClasses
       MultiWayIf
-      NamedFieldPuns
       NoImplicitPrelude
       OverloadedStrings
       PatternSynonyms
-      Rank2Types
-      RankNTypes
-      ScopedTypeVariables
-      StandaloneDeriving
-      TupleSections
-      TypeApplications
+      StrictData
       TypeFamilies
       TypeFamilyDependencies
-      TypeOperators
   ghc-options: -Wall -Wcompat -Wincomplete-record-updates -fhide-source-paths -fprint-potential-instances -fno-warn-partial-type-signatures -optP-Wno-nonportable-include-path -threaded -rtsopts -with-rtsopts=-N -fno-warn-orphans -fno-warn-missing-signatures -fno-warn-incomplete-uni-patterns -fno-warn-type-defaults -optP-Wno-nonportable-include-path
   build-depends:
       base >=4.14 && <5
@@ -144,4 +112,4 @@
     , transformers >=0.5 && <2
     , universum ==1.*
     , unordered-containers >=0.1 && <1
-  default-language: Haskell2010
+  default-language: GHC2021
diff --git a/src/Data/Registry/Hedgehog.hs b/src/Data/Registry/Hedgehog.hs
--- a/src/Data/Registry/Hedgehog.hs
+++ b/src/Data/Registry/Hedgehog.hs
@@ -27,10 +27,14 @@
     genNonEmptyMapOf,
     genHashMapOf,
     setDistinctPairOf,
+    setDistinctPairOfOn,
     setDistinctTripleOf,
+    setDistinctTripleOfOn,
     -- combinators to compose different types of generators
     distinctPairOf,
+    distinctPairOfOn,
     distinctTripleOf,
+    distinctTripleOfOn,
     eitherOf,
     hashMapOf,
     listOf,
@@ -61,7 +65,6 @@
 import Data.Maybe as Maybe
 import Data.Registry
 import Data.Registry.Internal.Hedgehog
-import Data.Registry.Internal.Types
 import Data.Set as Set (fromList)
 import Hedgehog
 import Hedgehog.Gen as Gen
@@ -92,7 +95,7 @@
 setGen = tweak @(Gen a) . const
 
 -- | Specialize a generator in a given context
-specializeGen :: forall a b ins out. (Typeable a, Typeable b) => Gen b -> Registry ins out -> Registry ins out
+specializeGen :: forall (a :: Type) b ins out. (Typeable a, Typeable b) => Gen b -> Registry ins out -> Registry ins out
 specializeGen = specialize @(Gen a) @(Gen b)
 
 -- | Add a generator for a list of elements
@@ -147,17 +150,25 @@
 setDistinctPairOf :: forall a. (Typeable a, Eq a) => Registry _ _ -> Registry _ _
 setDistinctPairOf r = fun (distinctPairOf @a) +: r
 
+-- | Add the generation of a pair of distinct elements, according to one of their part
+setDistinctPairOfOn :: forall a b. (Typeable a, Eq b) => (a -> b) -> Registry _ _ -> Registry _ _
+setDistinctPairOfOn f r = fun (distinctPairOfOn @a f) +: r
+
 -- | Add the generation of a triple of distinct elements
 setDistinctTripleOf :: forall a. (Typeable a, Eq a) => Registry _ _ -> Registry _ _
 setDistinctTripleOf r = fun (distinctTripleOf @a) +: r
 
+-- | Add the generation of a triple of distinct elements, according to one of their part
+setDistinctTripleOfOn :: forall a b. (Typeable a, Eq b) => (a -> b) -> Registry _ _ -> Registry _ _
+setDistinctTripleOfOn f r = fun (distinctTripleOfOn @a f) +: r
+
 -- | Make sure there is always one element of a given type in a list of elements
-makeNonEmpty :: forall a ins out. (Typeable a) => Registry ins out -> Registry ins out
-makeNonEmpty r =
+makeNonEmpty :: forall (a :: Type) ins out. (Typeable a) => Registry ins out -> Registry ins out
+makeNonEmpty r = do
   -- extract a generator for one element only
   let genA = genWith @a r
-   in -- add that element in front of a list of generated elements
-      tweak @(Gen [a]) (\genAs -> (:) <$> genA <*> genAs) r
+  -- add that element in front of a list of generated elements
+  tweak @(Gen [a]) (\genAs -> (:) <$> genA <*> genAs) r
 
 -- * CONTAINERS COMBINATORS
 
@@ -227,8 +238,16 @@
 
 -- | Make a generator for a pair of distinct values
 distinctPairOf :: forall a. (Eq a) => Gen a -> Gen (a, a)
-distinctPairOf genA = Gen.filterT (uncurry (/=)) $ (,) <$> genA <*> genA
+distinctPairOf = distinctPairOfOn identity
 
+-- | Make a generator for a pair of distinct values according to one of their part
+distinctPairOfOn :: forall a b. (Eq b) => (a -> b) -> Gen a -> Gen (a, a)
+distinctPairOfOn f genA = Gen.filterT (\(a1, a2) -> f a1 /= f a2) $ (,) <$> genA <*> genA
+
 -- | Make a generator for a triple of distinct values
 distinctTripleOf :: forall a. (Eq a) => Gen a -> Gen (a, a, a)
-distinctTripleOf genA = Gen.filterT (\(a1, a2, a3) -> a1 /= a2 && a2 /= a3 && a1 /= a3) $ (,,) <$> genA <*> genA <*> genA
+distinctTripleOf = distinctTripleOfOn identity
+
+-- | Make a generator for a triple of distinct values according to one of their part
+distinctTripleOfOn :: forall a b. (Eq b) => (a -> b) -> Gen a -> Gen (a, a, a)
+distinctTripleOfOn f genA = Gen.filterT (\(a1, a2, a3) -> f a1 /= f a2 && f a2 /= f a3 && f a1 /= f a3) $ (,,) <$> genA <*> genA <*> genA
diff --git a/src/Data/Registry/Hedgehog/TH.hs b/src/Data/Registry/Hedgehog/TH.hs
--- a/src/Data/Registry/Hedgehog/TH.hs
+++ b/src/Data/Registry/Hedgehog/TH.hs
@@ -1,6 +1,10 @@
 {-# LANGUAGE DataKinds #-}
 
-module Data.Registry.Hedgehog.TH where
+module Data.Registry.Hedgehog.TH
+  ( GeneratorOptions (..),
+    module Data.Registry.Hedgehog.TH,
+  )
+where
 
 import Control.Monad.Fail (fail)
 import Data.Registry
@@ -9,6 +13,12 @@
 import Language.Haskell.TH.Syntax
 import Protolude
 
+makeGenerators :: Name -> ExpQ
+makeGenerators = makeGeneratorsWith defaultGeneratorOptions
+
+makeGeneratorsUnchecked :: Name -> ExpQ
+makeGeneratorsUnchecked = makeGeneratorsWith defaultGeneratorOptions {checked = False}
+
 -- | Make a registry containing generators for an ADT
 --   We  want to generate the following
 --
@@ -18,20 +28,20 @@
 --
 -- genEmployeeStatus :: Gen Chooser -> Gen (Tag "permanent" EmployeeStatus) -> Gen (Tag "temporary" EmployeeStatus) -> Gen EmployeeStatus
 -- genEmployeeStatus chooser g1 g2 = chooseOne chooser [fmap unTag1, fmap unTag g2]
-makeGenerators :: Name -> ExpQ
-makeGenerators genType = do
+makeGeneratorsWith :: GeneratorOptions -> Name -> ExpQ
+makeGeneratorsWith options genType = do
   info <- reify genType
   case info of
     TyConI (NewtypeD _context _name _typeVars _kind constructor _deriving) -> do
       constructorType <- nameOf constructor
-      app (genFunOf (conE constructorType)) (varE (mkName "emptyRegistry"))
+      genFunOf (conE constructorType)
     TyConI (DataD _context _name _typeVars _kind [constructor] _deriving) -> do
       constructorType <- nameOf constructor
-      app (genFunOf (conE constructorType)) (varE (mkName "emptyRegistry"))
+      genFunOf (conE constructorType)
     TyConI (DataD _context name _typeVars _kind constructors _deriving) -> do
       selector <- makeSelectGenerator name constructors
       generators <- traverse makeConstructorGenerator constructors
-      assembleGeneratorsToRegistry selector generators
+      assembleGeneratorsToRegistry options selector generators
     other -> do
       qReport True ("can not create generators for this kind of data type at the moment. Got: " <> show other)
       fail "generators creation failed"
diff --git a/src/Data/Registry/Internal/TH.hs b/src/Data/Registry/Internal/TH.hs
--- a/src/Data/Registry/Internal/TH.hs
+++ b/src/Data/Registry/Internal/TH.hs
@@ -13,6 +13,18 @@
 import Protolude hiding (Type)
 import Prelude (last)
 
+-- | Options for changing the generated TH code
+--    if checked = True then we use the <: operator which checks input
+--    otherwise we use the <+ operator which doesn't check inputs
+newtype GeneratorOptions = GeneratorOptions
+  { checked :: Bool
+  }
+  deriving (Eq, Show)
+
+-- | By default we want to typecheck the generators
+defaultGeneratorOptions :: GeneratorOptions
+defaultGeneratorOptions = GeneratorOptions True
+
 -- | Create a generator for selecting between constructors of an ADT
 --   One parameter is a Gen Chooser in order to be able to later on
 --   switch the selection strategy
@@ -82,20 +94,22 @@
 -- | runQ [| fun g +: genFun e +: genFun f|]
 --   InfixE (Just (AppE (VarE Data.Registry.Registry.fun) (UnboundVarE g))) (VarE +:) (Just (InfixE (Just (AppE (VarE Data.Registry.Hedgehog.genFun) (UnboundVarE e)))
 --  (VarE Data.Registry.Registry.+:) (Just (AppE (VarE Data.Registry.Hedgehog.genFun) (UnboundVarE f)))))
-assembleGeneratorsToRegistry :: Exp -> [Exp] -> ExpQ
-assembleGeneratorsToRegistry _ [] =
-  fail "generators creation failed"
-assembleGeneratorsToRegistry selectorGenerator [g] =
-  app (genFunOf (pure g)) $
-    app (funOf (pure selectorGenerator)) $
-      app (genFunOf (varE (mkName "choiceChooser"))) (varE (mkName "emptyRegistry"))
---
-assembleGeneratorsToRegistry selectorGenerator (g : gs) =
-  app (genFunOf (pure g)) (assembleGeneratorsToRegistry selectorGenerator gs)
+assembleGeneratorsToRegistry :: GeneratorOptions -> Exp -> [Exp] -> ExpQ
+assembleGeneratorsToRegistry options selectorGenerator generators =
+  app options (funOf (pure selectorGenerator)) $
+    app options (genFunOf (varE (mkName "choiceChooser"))) $
+      go generators
+  where
+    go [] = fail "generators creation failed"
+    go [g] = genFunOf (pure g)
+    go (g:gs) =
+      app options (genFunOf (pure g)) $
+        go gs
 
-app :: ExpQ -> ExpQ -> ExpQ
-app e1 e2 =
-  infixE (Just e1) (varE (mkName "+:")) (Just e2)
+app :: GeneratorOptions -> ExpQ -> ExpQ -> ExpQ
+app options e1 e2 = do
+  let op = if checked options then "<:" else "<+"
+  infixE (Just e1) (varE (mkName op)) (Just e2)
 
 genFunOf :: ExpQ -> ExpQ
 genFunOf = appE (varE (mkName "genFun"))
diff --git a/test/Test/Data/Registry/Generators.hs b/test/Test/Data/Registry/Generators.hs
--- a/test/Test/Data/Registry/Generators.hs
+++ b/test/Test/Data/Registry/Generators.hs
@@ -26,7 +26,7 @@
     <: $(makeGenerators ''EmployeeStatus)
     <: $(makeGenerators ''DepartmentName)
     <: $(makeGenerators ''EmployeeName)
-    <: fun (maybeOf @Int)
+    <: genMaybeOf @Int
     -- we can generate Lists or Maybe of elements
     <: genVal genInt
     <: genVal genText
diff --git a/test/Test/Tutorial/Exercise2.hs b/test/Test/Tutorial/Exercise2.hs
--- a/test/Test/Tutorial/Exercise2.hs
+++ b/test/Test/Tutorial/Exercise2.hs
@@ -22,7 +22,7 @@
     <: fun (listOf @Employee)
     <: genFun Employee
     <: genFun genEmployeeStatus
-    <: fun (maybeOf @Int)
+    <: genMaybeOf @Int
     <: genVal genInt
     <: genVal genText
 
diff --git a/test/Test/Tutorial/Exercise3.hs b/test/Test/Tutorial/Exercise3.hs
--- a/test/Test/Tutorial/Exercise3.hs
+++ b/test/Test/Tutorial/Exercise3.hs
@@ -16,7 +16,14 @@
 import Test.Tutorial.Exercise2 (registry)
 
 registry3 :: Registry _ _
-registry3 = $(makeGenerators ''EmployeeStatus) <: registry
+registry3 =
+  $(makeGenerators ''EmployeeStatus)
+    <: registry
+
+registry3Unchecked :: Registry _ _
+registry3Unchecked =
+  $(makeGeneratorsUnchecked ''EmployeeStatus)
+    <: registry
 
 forall :: forall a. (Typeable a, Show a) => PropertyT IO a
 forall = withFrozenCallStack $ forAll $ genWith @a registry3