diff --git a/gemstone.cabal b/gemstone.cabal
--- a/gemstone.cabal
+++ b/gemstone.cabal
@@ -7,7 +7,7 @@
 -- The package version. See the Haskell package versioning policy
 -- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for
 -- standards guiding when and how versions should be incremented.
-Version:             0.2
+Version:             0.2.1
 
 -- A short (one-line) description of the package.
 Synopsis:            A simple library of helpers for SDL+GL games.
@@ -80,7 +80,7 @@
                    , bitmap
                    , bitmap-opengl
                    , containers
-                   , lens
+                   , lens == 3.7.*
                    , linear == 0.9.*
                    , random
                    , stb-image