diff --git a/build.sbt b/build.sbt
index 1785a2dfe4..a86edbc97d 100644
--- a/build.sbt
+++ b/build.sbt
@@ -157,7 +157,6 @@ val codegenSettings = Seq(
   scalacOptions in ThisBuild ++= Seq(
     "-Ypartial-unification",
     "-Ydelambdafy:method",
-    "-Ywarn-unused-import",
     "-feature",
     "-unchecked",
     "-deprecation",
@@ -194,7 +193,10 @@ lazy val codegen = (project in file("modules/codegen"))
       "org.typelevel"               %% "cats-free"                    % catsVersion,
       "org.scala-lang.modules"      %% "scala-java8-compat"           % "0.9.0",
     ),
-    scalacOptions += "-language:higherKinds",
+    scalacOptions ++= List(
+      "-language:higherKinds",
+      "-Ywarn-unused-import",
+    ),
     bintrayRepository := {
       if (isSnapshot.value) "snapshots"
       else "releases"