diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,9 @@
 # Changelog for composite-dhall
 
+## v0.1.0.0
+
+* Bump to dhall 1.40 and use Op instance from that.
+
 ## v0.0.6.0
 
 * Fix exports for `F` and `CoF`.
diff --git a/composite-dhall.cabal b/composite-dhall.cabal
--- a/composite-dhall.cabal
+++ b/composite-dhall.cabal
@@ -5,7 +5,7 @@
 -- see: https://github.com/sol/hpack
 
 name:           composite-dhall
-version:        0.0.6.0
+version:        0.1.0.0
 synopsis:       Dhall instances for composite records.
 description:    Dhall instances for composite records.
 category:       Composite, Data, Dhall
@@ -41,7 +41,7 @@
   build-depends:
       base >=4.7 && <5
     , composite-base >=0.7.0.0 && <0.8
-    , dhall >=1.34.0 && <1.40
+    , dhall ==1.40.*
     , text >=1.0 && <1.4
     , vinyl >=0.13.0 && <0.14
   default-language: Haskell2010
@@ -58,7 +58,7 @@
       base >=4.7 && <5
     , composite-base >=0.7.0.0 && <0.8
     , composite-dhall
-    , dhall >=1.34.0 && <1.40
+    , dhall ==1.40.*
     , tasty
     , tasty-hunit
     , text >=1.0 && <1.4
diff --git a/src/Composite/Dhall.hs b/src/Composite/Dhall.hs
--- a/src/Composite/Dhall.hs
+++ b/src/Composite/Dhall.hs
@@ -185,12 +185,6 @@
             _ -> die
      in CoF <$> D.Decoder extract expected
 
-deriving newtype instance (D.ToDhall x) => D.FromDhall (Predicate x)
-
-deriving newtype instance (D.ToDhall x) => D.FromDhall (Equivalence x)
-
-deriving newtype instance (D.FromDhall b, D.ToDhall x) => D.FromDhall (Op b x)
-
 deriving via (F Maybe (s :-> x ': xs)) instance (KnownSymbol s, D.ToDhall (F Maybe xs), D.ToDhall x) => D.ToDhall (Rec Maybe (s :-> x ': xs))
 
 deriving via (F [] (s :-> x ': xs)) instance (KnownSymbol s, D.ToDhall (F [] xs), D.ToDhall x) => D.ToDhall (Rec [] (s :-> x ': xs))