diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
 # Revision history for hierarchical-env
 
+## 0.2.0.2 -- 2021-05-13
+* Add `Eq` `Ord` `Show` instances for `Extends`
+
 ## 0.2.0.1 -- 2021-05-08
 * Relax library dependency (`method`)
 
diff --git a/hierarchical-env.cabal b/hierarchical-env.cabal
--- a/hierarchical-env.cabal
+++ b/hierarchical-env.cabal
@@ -5,7 +5,7 @@
 -- http://haskell.org/cabal/users-guide/
 
 name:               hierarchical-env
-version:            0.2.0.1
+version:            0.2.0.2
 synopsis:           hierarchical environments for dependency injection
 description:
   This library provides scalable dependency injection for RIO monad
diff --git a/src/Control/Env/Hierarchical/Internal.hs b/src/Control/Env/Hierarchical/Internal.hs
--- a/src/Control/Env/Hierarchical/Internal.hs
+++ b/src/Control/Env/Hierarchical/Internal.hs
@@ -72,6 +72,7 @@
 
 -- | Wrapper that represents the super environment.
 newtype Extends env = Extends env
+  deriving (Eq, Ord, Show)
 
 {-# INLINE extendsL #-}
 extendsL :: Lens' (Extends x) x