diff --git a/.travis.yml b/.travis.yml
index bad97e97..fb70614f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -15,10 +15,15 @@ rvm:
   - 2.0.0
   - 2.1
   - 2.2
-  - 2.3.4
-  - 2.4.1
-  - rbx-3.81
+  - 2.3
+  - 2.4
+  - 2.5
+  - rbx-3.100
   - ruby-head
 
+matrix:
+  allow_failures:
+  - rvm: ruby-head
+
 notifications:
   email: false
diff --git a/redcarpet.gemspec b/redcarpet.gemspec
index 22891d36..aff67cfe 100644
--- a/redcarpet.gemspec
+++ b/redcarpet.gemspec
@@ -65,7 +65,7 @@ Gem::Specification.new do |s|
   s.executables = ["redcarpet"]
   s.require_paths = ["lib"]
 
-  s.add_development_dependency "rake", "~> 12.0"
+  s.add_development_dependency "rake", "~> 12.2.1"
   s.add_development_dependency "rake-compiler", "~> 1.0.3"
   s.add_development_dependency "test-unit", "~> 3.2.3"
 end