diff --git a/covariant/build.sbt.shared b/covariant/build.sbt.shared
index 569a6098..9fd12396 100644
--- a/covariant/build.sbt.shared
+++ b/covariant/build.sbt.shared
@@ -1,6 +1,6 @@
 libraryDependencies += "org.scalaz" %%% "scalaz-core" % "7.2.14"
 
-libraryDependencies += "org.scalaz" %%% "scalaz-effect" % "7.2.14" % Test
+libraryDependencies += "org.scalaz" %%% "scalaz-effect" % "7.2.31" % Test
 
 addCompilerPlugin("org.spire-math" %% "kind-projector" % "0.9.3")
 
diff --git a/invariant/build.sbt.shared b/invariant/build.sbt.shared
index 94a4df92..36d57c2b 100644
--- a/invariant/build.sbt.shared
+++ b/invariant/build.sbt.shared
@@ -1,6 +1,6 @@
 libraryDependencies += "org.scalaz" %%% "scalaz-core" % "7.2.14"
 
-libraryDependencies += "org.scalaz" %%% "scalaz-effect" % "7.2.14" % Test
+libraryDependencies += "org.scalaz" %%% "scalaz-effect" % "7.2.31" % Test
 
 addCompilerPlugin("org.spire-math" %% "kind-projector" % "0.9.3")