diff --git a/.travis.yml b/.travis.yml
index 88df2c50..9b138ddf 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -27,6 +27,11 @@ matrix:
       sudo: required
       services: docker
       env: DOCKER_IMAGE=ubuntu:16.04
+    - os: linux
+      dist: trusty
+      sudo: required
+      services: docker
+      env: DOCKER_IMAGE=ubuntu:16.04 SWIFT_SNAPSHOT=$SWIFT_DEVELOPMENT_SNAPSHOT
     - os: linux
       dist: trusty
       sudo: required
@@ -43,6 +48,10 @@ matrix:
     - os: osx
       osx_image: xcode10
       sudo: required
+    - os: osx
+      osx_image: xcode10.1
+      sudo: required
+      env: SWIFT_SNAPSHOT=$SWIFT_DEVELOPMENT_SNAPSHOT
 
 before_install:
   - git clone https://github.com/IBM-Swift/Package-Builder.git
diff --git a/Sources/KituraNet/ClientRequest.swift b/Sources/KituraNet/ClientRequest.swift
index c8271013..d5b7490d 100644
--- a/Sources/KituraNet/ClientRequest.swift
+++ b/Sources/KituraNet/ClientRequest.swift
@@ -475,7 +475,7 @@ public class ClientRequest {
         guard let data = authHeader.data(using: String.Encoding.utf8) else {
             return nil
         }
-        return "Basic \(data.base64EncodedString)"
+        return "Basic \(data.base64EncodedString())"
     }
 }