diff --git a/spdx.cabal b/spdx.cabal
--- a/spdx.cabal
+++ b/spdx.cabal
@@ -1,5 +1,5 @@
 name:                spdx
-version:             0.1.0.0
+version:             0.1.1.0
 synopsis:            SPDX license expression language
 description:         Implementation of <http://spdx.org/sites/spdx/files/SPDX-2.0.pdf SPDX> related functionality.
 homepage:            https://github.com/phadej/spdx
@@ -37,6 +37,8 @@
   ghc-options:         -Wall
   build-depends:       base              >=4.5 && <4.9,
                        transformers      >=0.3 && <0.5
+  if impl(ghc >= 7.4 && < 7.5)
+    build-depends: ghc-prim
 
 test-suite test
   type:                exitcode-stdio-1.0
diff --git a/src/Data/SPDX/Parser.hs b/src/Data/SPDX/Parser.hs
--- a/src/Data/SPDX/Parser.hs
+++ b/src/Data/SPDX/Parser.hs
@@ -15,6 +15,14 @@
 import Data.SPDX.Types
 import Data.SPDX.Licenses (licenseIdentifiers, licenseExceptions)
 
+#if !MIN_VERSION_base(4,6,0)
+import Control.Monad
+
+instance Applicative ReadP where
+  pure = return
+  (<*>) = ap
+#endif
+
 license :: ReadP LicenseId
 license = choice (map f licenseIdentifiers)
   where f l = l <$ string (getLicenseId l)