diff --git a/human-readable-duration.cabal b/human-readable-duration.cabal
--- a/human-readable-duration.cabal
+++ b/human-readable-duration.cabal
@@ -1,5 +1,5 @@
 name: human-readable-duration
-version: 0.2.0.2
+version: 0.2.0.3
 cabal-version: >=1.10
 build-type: Simple
 license: BSD3
@@ -35,14 +35,14 @@
     default-language: Haskell2010
     hs-source-dirs: src
 
-test-suite human-readable-duration-test
+test-suite doctest
     type: exitcode-stdio-1.0
-    main-is: Spec.hs
+    main-is: DocTest.hs
     build-depends:
         base >=4.7 && <5,
-        human-readable-duration >=0.2.0.2,
-        doctest >=0.9.12,
-        time >=1.5.0.0
+        Glob >=0.7,
+        human-readable-duration >=0.2.0.3,
+        doctest >=0.9.12
     default-language: Haskell2010
     hs-source-dirs: test
     ghc-options: -O2 -Wall
@@ -53,7 +53,7 @@
     build-depends:
         base >=4.7 && <5,
         criterion >=1.1.0.0,
-        human-readable-duration >=0.2.0.2
+        human-readable-duration >=0.2.0.3
     default-language: Haskell2010
     hs-source-dirs: bench
     ghc-options: -O2 -Wall -threaded
diff --git a/test/DocTest.hs b/test/DocTest.hs
new file mode 100644
--- /dev/null
+++ b/test/DocTest.hs
@@ -0,0 +1,7 @@
+module Main where
+
+import System.FilePath.Glob (glob)
+import Test.DocTest
+
+main :: IO ()
+main = glob "src/**/*.hs" >>= doctest
diff --git a/test/Spec.hs b/test/Spec.hs
deleted file mode 100644
--- a/test/Spec.hs
+++ /dev/null
@@ -1,7 +0,0 @@
-module Main where
-
-import Test.DocTest
-
-main :: IO ()
-main = doctest [ "src/Data/Duration.hs"
-               , "src/Data/Duration/Tutorial.hs"]