diff --git a/.travis.yml b/.travis.yml
index 13b5165e..d9d27489 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,7 +11,7 @@ jdk:
 
 env:
   - SCALAJS_VERSION=0.6.32
-  - SCALAJS_VERSION=1.1.1
+  - SCALAJS_VERSION=1.4.0
 
 script:
 - sbt ++$TRAVIS_SCALA_VERSION test
diff --git a/project/build.sbt b/project/build.sbt
index 37693b79..9e6ccdac 100644
--- a/project/build.sbt
+++ b/project/build.sbt
@@ -1,5 +1,5 @@
 // https://www.scala-js.org/news/2018/02/01/announcing-scalajs-1.0.0-M3/#cross-building-for-scalajs-06x-and-1x
-val scalaJSVersion = Option(System.getenv("SCALAJS_VERSION")).getOrElse("1.1.1")
+val scalaJSVersion = Option(System.getenv("SCALAJS_VERSION")).getOrElse("1.4.0")
 
 // https://github.com/portable-scala/sbt-crossproject
 addSbtPlugin("org.portable-scala" % "sbt-scalajs-crossproject" % "1.0.0")