diff --git a/extrapolate.cabal b/extrapolate.cabal
--- a/extrapolate.cabal
+++ b/extrapolate.cabal
@@ -1,5 +1,5 @@
 name:                extrapolate
-version:             0.4.0
+version:             0.4.1
 synopsis:            generalize counter-examples of test properties
 description:
   Extrapolate is a tool able to provide generalized counter-examples of test
@@ -78,7 +78,7 @@
 source-repository this
   type:            git
   location:        https://github.com/rudymatela/extrapolate
-  tag:             v0.4.0
+  tag:             v0.4.1
 
 library
   exposed-modules: Test.Extrapolate
@@ -97,7 +97,7 @@
   build-depends: base >= 4 && < 5
                , leancheck >= 0.9.1
                , template-haskell
-               , speculate >= 0.4.0
+               , speculate >= 0.4.1
                , express >= 0.1.0
   hs-source-dirs:      src
   default-language:    Haskell2010
diff --git a/src/Test/Extrapolate/Speculation.hs b/src/Test/Extrapolate/Speculation.hs
--- a/src/Test/Extrapolate/Speculation.hs
+++ b/src/Test/Extrapolate/Speculation.hs
@@ -26,7 +26,6 @@
 
 import Test.Speculate.Engine (theoryAndRepresentativesFromAtoms, classesFromSchemasAndVariables)
 import Test.Speculate.Reason (Thy)
-import Test.Speculate.Utils (boolTy, typesIn)
 
 import Test.Extrapolate.Utils
 import Test.Extrapolate.Expr
diff --git a/src/Test/Extrapolate/Testable.hs b/src/Test/Extrapolate/Testable.hs
--- a/src/Test/Extrapolate/Testable.hs
+++ b/src/Test/Extrapolate/Testable.hs
@@ -142,6 +142,6 @@
            $ [ eval (error msg :: [[Expr]]) tiersE
              | tiersE@(Value "tiers" _) <- is ]
     where
-    vs = sort . mapMaybe (maybeHoleOfTy is) . nubMergeMap (typesIn . typ) $ esU
+    vs = sort . mapMaybe (maybeHoleOfTy is) . typesInList . map typ $ esU
     esU = concat [evl e | e@(Value "background" _) <- is]
     msg = "canditateConditions: wrong type, not [[Expr]]"
diff --git a/stack-lts-11.yaml b/stack-lts-11.yaml
--- a/stack-lts-11.yaml
+++ b/stack-lts-11.yaml
@@ -5,8 +5,8 @@
 
 extra-deps:
 - leancheck-0.9.1
-- speculate-0.4.0
-- express-0.1.0
+- speculate-0.4.1
+- express-0.1.1
 
 flags: {}
 
diff --git a/stack.yaml b/stack.yaml
--- a/stack.yaml
+++ b/stack.yaml
@@ -5,8 +5,8 @@
 
 extra-deps:
 - leancheck-0.9.1
-- speculate-0.4.0
-- express-0.1.0
+- speculate-0.4.1
+- express-0.1.1
 
 flags: {}