diff --git a/nix-tree.cabal b/nix-tree.cabal
index 326018d..bc54d5c 100644
--- a/nix-tree.cabal
+++ b/nix-tree.cabal
@@ -36,11 +36,11 @@ common common-options
                       RankNTypes
                       ScopedTypeVariables
                       NumericUnderscores
-  other-modules:      PathStats
-                      StorePath
-                      App
-                      InvertedIndex
-                      Clipboard
+  other-modules:      NixTree.PathStats
+                      NixTree.StorePath
+                      NixTree.App
+                      Data.InvertedIndex
+                      NixTree.Clipboard
                       Paths_nix_tree
   autogen-modules:    Paths_nix_tree
   mixins:             base hiding (Prelude)
@@ -66,7 +66,7 @@ common common-options
 executable nix-tree
   import:             common-options
   ghc-options:        -Wunused-packages
-  main-is:            Main.hs
+  main-is:            NixTree/Main.hs
   hs-source-dirs:     src
   default-language:   Haskell2010
   build-depends:      base >= 4.11 && < 5
@@ -75,6 +75,7 @@ test-suite nix-tree-tests
   import:           common-options
   type:             exitcode-stdio-1.0
   hs-source-dirs:   test/ src/
+  other-modules:    Test.Data.InvertedIndex
   main-is:          Test.hs
   build-depends:    base >=4.11 && < 5
                   , hedgehog
diff --git a/src/InvertedIndex.hs b/src/Data/InvertedIndex.hs
similarity index 98%
rename from src/InvertedIndex.hs
rename to src/Data/InvertedIndex.hs
index 2c49fa5..583b11c 100644
--- a/src/InvertedIndex.hs
+++ b/src/Data/InvertedIndex.hs
@@ -1,4 +1,4 @@
-module InvertedIndex
+module Data.InvertedIndex
   ( InvertedIndex,
     iiFromList,
     iiInsert,
diff --git a/src/App.hs b/src/NixTree/App.hs
similarity index 99%
rename from src/App.hs
rename to src/NixTree/App.hs
index f739a48..4c0c085 100644
--- a/src/App.hs
+++ b/src/NixTree/App.hs
@@ -1,20 +1,20 @@
-module App (run, helpText) where
+module NixTree.App (run, helpText) where
 
 import qualified Brick as B
 import qualified Brick.BChan as B
 import qualified Brick.Widgets.Border as B
 import qualified Brick.Widgets.Center as B
 import qualified Brick.Widgets.List as B
-import qualified Clipboard
 import Control.Concurrent
+import Data.InvertedIndex
 import qualified Data.List.NonEmpty as NE
 import qualified Data.Map as Map
 import qualified Data.Sequence as S
 import qualified Data.Set as Set
 import qualified Data.Text as T
 import qualified Graphics.Vty as V
-import InvertedIndex
-import PathStats
+import qualified NixTree.Clipboard as Clipboard
+import NixTree.PathStats
 import qualified System.Clock as Clock
 import qualified System.HrfSize as HRF
 
@@ -335,7 +335,7 @@ yankToClipboard p =
             ( T.intercalate "\n" $
                 "Cannot copy to clipboard: " :
                 map ("  " <>) errs
-                ++ ["Please report this as a bug."]
+                  ++ ["Please report this as a bug."]
             )
 
 renderMainScreen :: AppEnv s -> B.Widget Widgets
diff --git a/src/Clipboard.hs b/src/NixTree/Clipboard.hs
similarity index 95%
rename from src/Clipboard.hs
rename to src/NixTree/Clipboard.hs
index 266e5a7..bbe4bfe 100644
--- a/src/Clipboard.hs
+++ b/src/NixTree/Clipboard.hs
@@ -1,4 +1,4 @@
-module Clipboard
+module NixTree.Clipboard
   ( copy,
   )
 where
@@ -27,7 +27,7 @@ runCmd txt (cmd, args) =
       Right (Just (ExitSuccess, _, _)) -> Right ()
       Right (Just (ExitFailure e, out, err)) ->
         Left $
-             "failed with exit code "
+          "failed with exit code "
             <> show e
             <> ", "
             <> "stdout: "
diff --git a/src/Main.hs b/src/NixTree/Main.hs
similarity index 98%
rename from src/Main.hs
rename to src/NixTree/Main.hs
index 49cf940..79a76f4 100644
--- a/src/Main.hs
+++ b/src/NixTree/Main.hs
@@ -1,10 +1,10 @@
 module Main where
 
-import App
+import NixTree.App
 import Control.Concurrent (forkIO)
 import qualified Data.HashMap.Strict as HM
 import Data.Version (showVersion)
-import PathStats
+import NixTree.PathStats
 import Paths_nix_tree (version)
 import System.Directory (canonicalizePath, doesDirectoryExist, getHomeDirectory)
 import System.Environment (getArgs)
diff --git a/src/PathStats.hs b/src/NixTree/PathStats.hs
similarity index 98%
rename from src/PathStats.hs
rename to src/NixTree/PathStats.hs
index c822b03..17f662c 100644
--- a/src/PathStats.hs
+++ b/src/NixTree/PathStats.hs
@@ -1,9 +1,9 @@
-module PathStats
+module NixTree.PathStats
   ( PathStats (..),
     calculatePathStats,
     whyDepends,
     shortestPathTo,
-    module StorePath,
+    module NixTree.StorePath,
   )
 where
 
@@ -11,7 +11,7 @@ import Data.List (minimumBy)
 import qualified Data.List.NonEmpty as NE
 import qualified Data.Map.Lazy as M
 import qualified Data.Set as S
-import StorePath
+import NixTree.StorePath
 
 data IntermediatePathStats s = IntermediatePathStats
   { ipsAllRefs :: M.Map (StoreName s) (StorePath s (StoreName s) ())
diff --git a/src/StorePath.hs b/src/NixTree/StorePath.hs
similarity index 99%
rename from src/StorePath.hs
rename to src/NixTree/StorePath.hs
index 7a6b155..664ae9f 100644
--- a/src/StorePath.hs
+++ b/src/NixTree/StorePath.hs
@@ -1,4 +1,4 @@
-module StorePath
+module NixTree.StorePath
   ( StoreName (..),
     storeNameToPath,
     storeNameToText,
diff --git a/test/Test.hs b/test/Test.hs
index 0693f93..2687e58 100644
--- a/test/Test.hs
+++ b/test/Test.hs
@@ -2,39 +2,11 @@
 
 module Main where
 
-import qualified Data.Map as Map
-import qualified Data.Text as Text
 import Hedgehog
-import qualified Hedgehog.Gen as Gen
 import Hedgehog.Main
-import qualified Hedgehog.Range as Range
-import InvertedIndex
-
-prop_inverted_index :: Property
-prop_inverted_index = withDiscards 10000 . withTests 10000 . property $ do
-  haystack <-
-    forAll $
-      Gen.map
-        (Range.linear 0 100)
-        ( (,)
-            <$> Gen.text (Range.linear 0 10) Gen.alphaNum
-            <*> Gen.int (Range.linear 0 100)
-        )
-
-  needle <-
-    forAll $
-      (Gen.text (Range.linear 0 5) Gen.alphaNum)
-
-  let ii = iiFromList (Map.toList haystack)
-  annotateShow ii
-
-  let expected =
-        haystack
-          & Map.filterWithKey
-            (\t _ -> Text.toLower needle `Text.isInfixOf` Text.toLower t)
-      actual = iiSearch needle ii
-
-  expected === actual
+import qualified Test.Data.InvertedIndex
 
 main :: IO ()
-main = defaultMain [checkParallel $$(discover)]
+main =
+  defaultMain . map checkParallel $
+    [Test.Data.InvertedIndex.tests]
diff --git a/test/Test/Data/InvertedIndex.hs b/test/Test/Data/InvertedIndex.hs
new file mode 100644
index 0000000..dfd73ae
--- /dev/null
+++ b/test/Test/Data/InvertedIndex.hs
@@ -0,0 +1,39 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+module Test.Data.InvertedIndex (tests) where
+
+import Data.InvertedIndex
+import qualified Data.Map as Map
+import qualified Data.Text as Text
+import Hedgehog
+import qualified Hedgehog.Gen as Gen
+import qualified Hedgehog.Range as Range
+
+prop_inverted_index :: Property
+prop_inverted_index = withDiscards 10000 . withTests 10000 . property $ do
+  haystack <-
+    forAll $
+      Gen.map
+        (Range.linear 0 100)
+        ( (,)
+            <$> Gen.text (Range.linear 0 10) Gen.alphaNum
+            <*> Gen.int (Range.linear 0 100)
+        )
+
+  needle <-
+    forAll $
+      (Gen.text (Range.linear 0 5) Gen.alphaNum)
+
+  let ii = iiFromList (Map.toList haystack)
+  annotateShow ii
+
+  let expected =
+        haystack
+          & Map.filterWithKey
+            (\t _ -> Text.toLower needle `Text.isInfixOf` Text.toLower t)
+      actual = iiSearch needle ii
+
+  expected === actual
+
+tests :: Group
+tests = $$(discover)
diff --git a/test/Test/Data/Test.hs b/test/Test/Data/Test.hs
new file mode 100644
index 0000000..ee9f19d
--- /dev/null
+++ b/test/Test/Data/Test.hs
@@ -0,0 +1,37 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+module Test.Data.InvertedIndex where
+
+import Data.InvertedIndex
+import qualified Data.Map as Map
+import qualified Data.Text as Text
+import Hedgehog
+import qualified Hedgehog.Gen as Gen
+import Hedgehog.Main
+import qualified Hedgehog.Range as Range
+
+prop_inverted_index :: Property
+prop_inverted_index = withDiscards 10000 . withTests 10000 . property $ do
+  haystack <-
+    forAll $
+      Gen.map
+        (Range.linear 0 100)
+        ( (,)
+            <$> Gen.text (Range.linear 0 10) Gen.alphaNum
+            <*> Gen.int (Range.linear 0 100)
+        )
+
+  needle <-
+    forAll $
+      (Gen.text (Range.linear 0 5) Gen.alphaNum)
+
+  let ii = iiFromList (Map.toList haystack)
+  annotateShow ii
+
+  let expected =
+        haystack
+          & Map.filterWithKey
+            (\t _ -> Text.toLower needle `Text.isInfixOf` Text.toLower t)
+      actual = iiSearch needle ii
+
+  expected === actual