diff --git a/.travis.yml b/.travis.yml
index 1c040215..fb6d1e7d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,6 @@
 language: scala
 scala:
-  - 2.13.2
+  - 2.13.3
 
 jdk:
   - openjdk8
diff --git a/build.sbt b/build.sbt
index 7b9d8abf..e5eb90f2 100644
--- a/build.sbt
+++ b/build.sbt
@@ -17,7 +17,7 @@ val scalafixSettings = Seq(
 
 val sharedSettings = Seq(
   organization := "com.github.eikek",
-  scalaVersion := "2.13.2",
+  scalaVersion := "2.13.3",
   scalacOptions ++= Seq(
     "-deprecation",
     "-encoding",
@@ -26,7 +26,8 @@ val sharedSettings = Seq(
     "-feature",
     "-Werror", // fail when there are warnings
     "-unchecked",
-    "-Xlint:_",
+    // remove -byname-implicit, once https://github.com/scala/bug/issues/12072 is resolved
+    "-Xlint:-byname-implicit,_",
     "-Wdead-code",
     "-Wunused",
     "-Wvalue-discard",
diff --git a/modules/convert/src/test/scala/docspell/convert/FileChecks.scala b/modules/convert/src/test/scala/docspell/convert/FileChecks.scala
index 60e235f0..0f6f17d8 100644
--- a/modules/convert/src/test/scala/docspell/convert/FileChecks.scala
+++ b/modules/convert/src/test/scala/docspell/convert/FileChecks.scala
@@ -18,7 +18,7 @@ trait FileChecks {
       Files.exists(p) && Files.size(p) > 0
 
     def isType(mime: MimeType): Boolean =
-      TikaMimetype.detect[IO](p).map(_ == mime).unsafeRunSync
+      TikaMimetype.detect[IO](p).map(_ == mime).unsafeRunSync()
 
     def isPDF: Boolean =
       isType(MimeType.pdf)
diff --git a/modules/convert/src/test/scala/docspell/convert/extern/ExternConvTest.scala b/modules/convert/src/test/scala/docspell/convert/extern/ExternConvTest.scala
index ff3eefac..d0f6c8b7 100644
--- a/modules/convert/src/test/scala/docspell/convert/extern/ExternConvTest.scala
+++ b/modules/convert/src/test/scala/docspell/convert/extern/ExternConvTest.scala
@@ -41,7 +41,7 @@ object ExternConvTest extends SimpleTestSuite with FileChecks {
             assert(p.isNonEmpty && p.isPDF)
           }
         )
-        .unsafeRunSync
+        .unsafeRunSync()
   }
 
   test("convert office to pdf") {
@@ -69,7 +69,7 @@ object ExternConvTest extends SimpleTestSuite with FileChecks {
             assert(p.isNonEmpty && p.isPDF)
           }
         )
-        .unsafeRunSync
+        .unsafeRunSync()
   }
 
   test("convert image to pdf") {
@@ -98,7 +98,7 @@ object ExternConvTest extends SimpleTestSuite with FileChecks {
             assert(txt.isNonEmpty && txt.isPlainText)
           }
         )
-        .unsafeRunSync
+        .unsafeRunSync()
   }
 
 }
diff --git a/modules/files/src/test/scala/docspell/files/TestFiles.scala b/modules/files/src/test/scala/docspell/files/TestFiles.scala
index 1ee01c9a..b415de1c 100644
--- a/modules/files/src/test/scala/docspell/files/TestFiles.scala
+++ b/modules/files/src/test/scala/docspell/files/TestFiles.scala
@@ -20,10 +20,10 @@ object TestFiles {
   lazy val letterDEText =
     ExampleFiles.letter_de_txt
       .readText[IO](8 * 1024, blocker)
-      .unsafeRunSync
+      .unsafeRunSync()
 
   lazy val letterENText =
     ExampleFiles.letter_en_txt
       .readText[IO](8 * 1024, blocker)
-      .unsafeRunSync
+      .unsafeRunSync()
 }
diff --git a/modules/files/src/test/scala/docspell/files/ZipTest.scala b/modules/files/src/test/scala/docspell/files/ZipTest.scala
index 3f267395..7fce9d50 100644
--- a/modules/files/src/test/scala/docspell/files/ZipTest.scala
+++ b/modules/files/src/test/scala/docspell/files/ZipTest.scala
@@ -29,6 +29,6 @@ object ZipTest extends SimpleTestSuite {
       }
       .compile
       .drain
-      .unsafeRunSync
+      .unsafeRunSync()
   }
 }