diff --git a/Tests/TestAeson.hs b/Tests/TestAeson.hs
new file mode 100644
--- /dev/null
+++ b/Tests/TestAeson.hs
@@ -0,0 +1,72 @@
+-- | Test encoding and decoding options.
+
+{-# LANGUAGE TemplateHaskell, ExtendedDefaultRules #-}
+{-# OPTIONS_GHC -Wno-orphans #-}
+
+module TestAeson where
+
+import Test.Framework
+import Test.Framework.TH
+import Test.Framework.Providers.QuickCheck2 (testProperty)
+import Test.QuickCheck
+
+import Data.String (String)
+
+import Lawless
+import Aeson
+import Text
+import Generics
+
+import Data.Text (pack)
+
+default (Text)
+
+data TestData = TestData
+    {
+        _tdName ∷ Text,
+        _tdCount ∷ Integer
+    } deriving (Show, Eq, Ord, Generic)
+makeLenses ''TestData
+instance ToJSON TestData where
+    toEncoding = moludeToJSONEncoding
+instance FromJSON TestData where
+    parseJSON = moludeParseJSON
+
+instance Arbitrary Text where
+    arbitrary = pack <$> arbitrary
+
+instance Arbitrary TestData where
+    arbitrary = TestData <$> arbitrary <*> arbitrary
+
+prop_TestEncodingSimple :: TestData -> Property
+prop_TestEncodingSimple (td :: TestData) =
+    let
+        enc = encode td
+
+        dec ∷ Either String TestData
+        dec = eitherDecode enc
+    in
+        collect "dec ∘ enc ≍ id" $ isn't _Left dec
+
+data Cluster = Cluster
+    {
+        _clName ∷ Text,
+        _clRegion ∷ Text
+    } deriving (Show, Eq, Ord, Generic)
+instance ToJSON Cluster where
+    toEncoding = moludeToJSONEncoding
+instance FromJSON Cluster where
+    parseJSON = moludeParseJSON
+
+data Schema1 = Schema1
+    {
+        _sc1Name ∷ Text,
+        _sc1Cluster ∷ Cluster
+    } deriving (Show, Eq, Ord, Generic)
+instance ToJSON Schema1 where
+    toEncoding = moludeToJSONEncoding
+instance FromJSON Schema1 where
+    parseJSON = moludeParseJSON
+
+properties ∷ Test
+properties = $(testGroupGenerator)
diff --git a/Tests/TestSepList.hs b/Tests/TestSepList.hs
new file mode 100644
--- /dev/null
+++ b/Tests/TestSepList.hs
@@ -0,0 +1,35 @@
+{-# LANGUAGE TemplateHaskell #-}
+{-# OPTIONS_GHC -Wno-orphans #-}
+
+module TestSepList (properties) where
+
+import Lawless
+import Textual
+
+import Test.Framework
+import Test.Framework.TH
+import Test.Framework.Providers.QuickCheck2 (testProperty)
+import Test.QuickCheck
+
+import qualified Data.ByteString.Lazy as L
+
+import Data.Binary
+
+
+instance Arbitrary (SepList Char) where
+  arbitrary = foldl1Of folded (<>) . over traversed sepList <$> listOf1 arbitrary
+
+prop_Semigroup :: SepList Char -> SepList Char -> Property
+prop_Semigroup (a :: SepList Char) (b :: SepList Char) =
+  (a <> b) ^. slItems === (a ^. slItems) <> (b ^. slItems)
+
+prop_Serialize :: SepList Char -> Property
+prop_Serialize (a :: SepList Char) =
+  let
+    sz = L.toStrict $ encode a
+    de = decode $ L.fromStrict sz
+  in
+    (de ^. slItems) === (a ^. slItems)
+
+properties ∷ Test
+properties = $(testGroupGenerator)
diff --git a/Tests/TestTemporary.hs b/Tests/TestTemporary.hs
new file mode 100644
--- /dev/null
+++ b/Tests/TestTemporary.hs
@@ -0,0 +1,41 @@
+{-# LANGUAGE TemplateHaskell #-}
+{-# OPTIONS_GHC -Wno-orphans #-}
+
+{-|
+Module:             TestTemporary
+Description:        Test that temporary files are unbuffered and binary.
+Copyright:          © 2016 All rights reserved.
+License:            GPL-3
+Maintainer:         Evan Cofsky <>
+Stability:          experimental
+Portability:        POSIX
+-}
+
+module TestTemporary where
+
+import Lawless
+import Test.Framework
+import Test.Framework.TH
+import Test.Framework.Providers.QuickCheck2 (testProperty)
+import Test.QuickCheck
+import Text
+import Paths
+import Temporary
+import qualified Data.ByteString as B
+import System.IO hiding (utf8)
+import Test.QuickCheck.Monadic
+import Data.Text.Encoding (encodeUtf8)
+
+instance Arbitrary Text where
+    arbitrary = view packed <$> listOf1 arbitrary
+
+prop_CheckBuffering (line ∷ Text) = monadicIO $ do
+    let l = encodeUtf8 line
+    m ← run $ withTempHandle $(mkRelFile "testTemp") $ \h → do
+        B.hPut h l
+        hSeek h AbsoluteSeek 0
+        B.hGetContents h
+    assert (l ≡ m)
+
+properties ∷ Test
+properties = $(testGroupGenerator)
diff --git a/Tests/TestTime.hs b/Tests/TestTime.hs
new file mode 100644
--- /dev/null
+++ b/Tests/TestTime.hs
@@ -0,0 +1,52 @@
+{-# LANGUAGE TemplateHaskell #-}
+{-# OPTIONS_GHC -Wno-orphans #-}
+
+module TestTime where
+
+import Test.Framework
+import Test.Framework.TH
+import Test.Framework.Providers.QuickCheck2 (testProperty)
+import Test.QuickCheck
+
+import qualified Data.ByteString.Lazy as L
+
+import Data.Time.Clock
+import Data.Time.Calendar
+import Data.Binary
+
+import Lawless
+import Time
+
+instance Arbitrary Day where
+  arbitrary = toEnum <$> arbitrary
+
+instance Arbitrary DiffTime where
+  arbitrary = fromRational <$> suchThat arbitrary (\t -> t >= 0.0 && t <= 86401.0)
+
+instance Arbitrary UTCTime where
+  arbitrary =
+    UTCTime <$> arbitrary <*> arbitrary
+
+instance Arbitrary Time where
+  arbitrary = review _Time <$> arbitrary
+
+prop_PrismToTime :: UTCTime -> Property
+prop_PrismToTime (ut :: UTCTime) =
+  ut ^.re _Time ^. day === utctDay ut .&&.
+  ut ^.re _Time ^. time === utctDayTime ut
+
+prop_PrismFromTime :: Time -> Property
+prop_PrismFromTime (t :: Time) =
+  utctDay (t ^. _Time) === t ^. day .&&.
+  utctDayTime (t ^. _Time) === t ^. time
+
+prop_Serialize :: Time -> Property
+prop_Serialize (t :: Time) =
+  let
+    sz = L.toStrict $ encode t
+    de = decode $ L.fromStrict sz
+  in
+    de === t
+
+properties ∷ Test
+properties = $(testGroupGenerator)
diff --git a/liblawless.cabal b/liblawless.cabal
--- a/liblawless.cabal
+++ b/liblawless.cabal
@@ -1,5 +1,5 @@
 name:                liblawless
-version:             0.13.2
+version:             0.13.3
 synopsis:            Prelude based on protolude for GHC 8 and beyond.
 license:             GPL-3
 license-file:        LICENSE
@@ -11,6 +11,7 @@
 extra-source-files:
                    CHANGELOG
                    README.md
+                   Tests/*.hs
 cabal-version:       >=1.24
 description:
     A Prelude relpacement for GHC 8 with a focus on building
@@ -23,7 +24,7 @@
 source-repository this
   type:     git
   location: https://gitlab.com/misandrist/liblawless.git
-  tag: v0.13.2
+  tag: v0.13.3
 
 library
   exposed-modules: