diff --git a/.travis.yml b/.travis.yml
index c63357ee..66fca4df 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,6 +5,7 @@ branches:
   only:
     - master
     - 5.6-dev
+    - 5.7-dev
 git:
   depth: 1
 
@@ -27,6 +28,14 @@ matrix:
           packages: ['g++-8']
       env:
         - MATRIX_EVAL="CXX_COMPILER=g++-8 C_COMPILER=gcc-8"
+    - os: linux
+      compiler: gcc
+      addons:
+        apt:
+          sources: ['ubuntu-toolchain-r-test']
+          packages: ['g++-9']
+      env:
+        - MATRIX_EVAL="CXX_COMPILER=g++-9 C_COMPILER=gcc-9"
 
     # clang on Linux
     - os: linux
@@ -53,6 +62,17 @@ matrix:
           packages: ['clang-8', "g++-7"]
       env:
         - MATRIX_EVAL="CXX_COMPILER=clang++-8 C_COMPILER=clang-8"
+    - os: linux
+      compiler: clang
+      addons:
+        apt:
+          sources:
+             - sourceline: 'ppa:ubuntu-toolchain-r/test'
+             - sourceline: 'deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-9 main'
+               key_url: 'https://apt.llvm.org/llvm-snapshot.gpg.key'
+          packages: ['clang-9', "g++-9"]
+      env:
+        - MATRIX_EVAL="CXX_COMPILER=clang++-9 C_COMPILER=clang-9"
         
     # clang on macOS
     - os: osx
@@ -65,6 +85,26 @@ matrix:
       compiler: clang
       env:
         - MATRIX_EVAL="CXX_COMPILER=clang++ C_COMPILER=clang"
+    - os: osx
+      osx_image: xcode10.3
+      compiler: clang
+      env:
+        - MATRIX_EVAL="CXX_COMPILER=clang++ C_COMPILER=clang"
+    - os: osx
+      osx_image: xcode11.1
+      compiler: clang
+      env:
+        - MATRIX_EVAL="CXX_COMPILER=clang++ C_COMPILER=clang"
+    - os: osx
+      osx_image: xcode11.2
+      compiler: clang
+      env:
+        - MATRIX_EVAL="CXX_COMPILER=clang++ C_COMPILER=clang"
+    - os: osx
+      osx_image: xcode11.3
+      compiler: clang
+      env:
+        - MATRIX_EVAL="CXX_COMPILER=clang++ C_COMPILER=clang"
 
 before_install:
    - eval "${MATRIX_EVAL}"