diff --git a/.travis.yml b/.travis.yml
index 485c803..72f5b54 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,7 @@ rvm:
   - 1.9.3
   - 2.0.0
   - 2.1.0
+  - 2.3.1
 
 env:
   matrix:
@@ -22,7 +23,8 @@ env:
     - PUPPET_GEM_VERSION="~> 4.1.0"
     - PUPPET_GEM_VERSION="~> 4.2.0"
     - PUPPET_GEM_VERSION="~> 4.3.0"
-    - PUPPET_GEM_VERSION="~> 4"
+    - PUPPET_GEM_VERSION="~> 4.4.0"
+    - PUPPET_GEM_VERSION="~> 4.5.0"
     - PUPPET_GEM_VERSION="~> 4" STRICT_VARIABLES="yes"
 
 sudo: false
@@ -51,9 +53,29 @@ matrix:
     - rvm: 1.8.7
       env: PUPPET_GEM_VERSION="~> 4.3.0"
     - rvm: 1.8.7
-      env: PUPPET_GEM_VERSION="~> 4"
+      env: PUPPET_GEM_VERSION="~> 4.4.0"
+    - rvm: 1.8.7
+      env: PUPPET_GEM_VERSION="~> 4.5.0"
     - rvm: 1.8.7
       env: PUPPET_GEM_VERSION="~> 4" STRICT_VARIABLES="yes"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3.1.0"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3.2.0"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3.3.0"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3.4.0"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3.5.0"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3.6.0"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3.7.0"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3.8.0"
+    - rvm: 2.3.1
+      env: PUPPET_GEM_VERSION="~> 3" FUTURE_PARSER="yes"
 
 notifications:
   email: false
diff --git a/Gemfile b/Gemfile
index 6134a7f..5b74df8 100644
--- a/Gemfile
+++ b/Gemfile
@@ -31,6 +31,9 @@ if RUBY_VERSION >= '1.8.7' and RUBY_VERSION < '1.9'
   gem 'rake', '~> 10.0'
 end
 
-if RUBY_VERSION >= '1.8.7' and RUBY_VERSION < '2.0'
-  gem 'json', '~> 1.0'
+if RUBY_VERSION < '2.0'
+  # json 2.x requires ruby 2.0. Lock to 1.8
+  gem 'json', '~> 1.8'
+  # json_pure 2.0.2 requires ruby 2.0. Lock to 2.0.1
+  gem 'json_pure', '= 2.0.1'
 end
diff --git a/README.md b/README.md
index 49e5a41..816b5db 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@ This module may be used with a simple `include ::ssh`
 
 This module has been tested to work on the following systems with Puppet
 versions v3, v3 with future parser and v4 with  Ruby versions 1.8.7 (Puppet v3
-only), 1.9.3, 2.0.0 and 2.1.0.
+only), 1.9.3, 2.0.0, 2.1.0 and 2.3.1 (Puppet v4 only).
 
  * Debian 7
  * EL 5