diff --git a/src/Data/Abstract/Environment.hs b/src/Data/Abstract/Environment.hs
index 77bc0b185..bdd2c4d94 100644
--- a/src/Data/Abstract/Environment.hs
+++ b/src/Data/Abstract/Environment.hs
@@ -37,7 +37,7 @@ import qualified Data.List.NonEmpty as NonEmpty
 -- | A LIFO stack of maps of names to addresses, representing a lexically-scoped evaluation environment.
 --   All behaviors can be assumed to be frontmost-biased: looking up "a" will check the most specific
 --   scope for "a", then the next, and so on.
-newtype Environment location value = Environment { unEnvironment :: NonEmpty (Map.Map Name (Address location value)) }
+newtype Environment location value = Environment { unEnvironment :: NonEmpty (Map.Map Name location) }
   deriving (Eq, Generic1, Ord, Show)
 
 instance Eq   location => Eq1   (Environment location) where liftEq        = genericLiftEq
@@ -49,8 +49,8 @@ instance Show location => Show1 (Environment location) where liftShowsPrec = gen
 --   same Name or you violate the axiom that toList . fromList == id.
 instance IsList (Environment location value) where
   type Item (Environment location value) = (Name, Address location value)
-  fromList xs                   = Environment (Map.fromList xs :| [])
-  toList (Environment (x :| _)) = Map.toList x
+  fromList xs                   = Environment (Map.fromList (second unAddress <$> xs) :| [])
+  toList (Environment (x :| _)) = second Address <$> Map.toList x
 
 mergeEnvs :: Environment location value -> Environment location value -> Environment location value
 mergeEnvs (Environment (a :| as)) (Environment (b :| bs)) =
@@ -87,7 +87,7 @@ mergeNewer (Environment a) (Environment b) =
 -- >>> pairs shadowed
 -- [(Name {unName = "foo"},Address {unAddress = Precise 1)]
 pairs :: Environment location value -> [(Name, Address location value)]
-pairs = Map.toList . fold . unEnvironment
+pairs = map (second Address) . Map.toList . fold . unEnvironment
 
 unpairs :: [(Name, Address location value)] -> Environment location value
 unpairs = fromList
@@ -97,11 +97,11 @@ unpairs = fromList
 -- >>> lookup (name "foo") shadowed
 -- Just (Address {unAddress = Precise 1})
 lookup :: Name -> Environment location value -> Maybe (Address location value)
-lookup k = foldMapA (Map.lookup k) . unEnvironment
+lookup k = fmap Address . foldMapA (Map.lookup k) . unEnvironment
 
 -- | Insert a 'Name' in the environment.
 insert :: Name -> Address location value -> Environment location value -> Environment location value
-insert name value (Environment (a :| as)) = Environment (Map.insert name value a :| as)
+insert name (Address value) (Environment (a :| as)) = Environment (Map.insert name value a :| as)
 
 -- | Remove a 'Name' from the environment.
 --