diff --git a/asynchronous/build.sbt.shared b/asynchronous/build.sbt.shared
index 4d24e094..1932ce48 100644
--- a/asynchronous/build.sbt.shared
+++ b/asynchronous/build.sbt.shared
@@ -1,4 +1,4 @@
-libraryDependencies += "org.scalatest" %%% "scalatest" % "3.0.3" % Test
+libraryDependencies += "org.scalatest" %%% "scalatest" % "3.0.9" % Test
 
 addCompilerPlugin("org.spire-math" %% "kind-projector" % "0.9.3")
 
diff --git a/covariant/build.sbt.shared b/covariant/build.sbt.shared
index 569a6098..310f4b9b 100644
--- a/covariant/build.sbt.shared
+++ b/covariant/build.sbt.shared
@@ -4,7 +4,7 @@ libraryDependencies += "org.scalaz" %%% "scalaz-effect" % "7.2.14" % Test
 
 addCompilerPlugin("org.spire-math" %% "kind-projector" % "0.9.3")
 
-libraryDependencies += "org.scalatest" %%% "scalatest" % "3.0.3" % Test
+libraryDependencies += "org.scalatest" %%% "scalatest" % "3.0.9" % Test
 
 libraryDependencies += "com.thoughtworks.future" %%% "future" % "2.0.0" % Test
 
diff --git a/invariant/build.sbt.shared b/invariant/build.sbt.shared
index 94a4df92..6eff8269 100644
--- a/invariant/build.sbt.shared
+++ b/invariant/build.sbt.shared
@@ -4,7 +4,7 @@ libraryDependencies += "org.scalaz" %%% "scalaz-effect" % "7.2.14" % Test
 
 addCompilerPlugin("org.spire-math" %% "kind-projector" % "0.9.3")
 
-libraryDependencies += "org.scalatest" %%% "scalatest" % "3.0.3" % Test
+libraryDependencies += "org.scalatest" %%% "scalatest" % "3.0.9" % Test
 
 scalacOptions += "-Xexperimental" // Enable SAM type for Scala 2.11
 
diff --git a/shared/build.sbt.shared b/shared/build.sbt.shared
index e225eeba..ab22d48e 100644
--- a/shared/build.sbt.shared
+++ b/shared/build.sbt.shared
@@ -1,4 +1,4 @@
-libraryDependencies += "org.scalatest" %%% "scalatest" % "3.0.3" % Test
+libraryDependencies += "org.scalatest" %%% "scalatest" % "3.0.9" % Test
 
 libraryDependencies += "com.thoughtworks.tryt" %%% "covariant" % "2.1.1" % Test