diff --git a/.travis.yml b/.travis.yml
index 43e58ac84..6eb7dba9d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,17 +1,19 @@
 language: ruby
 
 rvm:
-  - 2.3
-  - 2.4
+  # Let's build with the most relevant versions first:
   - 2.5
+  - 2.4
+  - 2.3
+  - ruby-head
 
 env:
   global:
     - COVERAGE=true JRUBY_OPTS=--debug
   matrix:
-    - MONGODB=3.2.18
-    - MONGODB=3.4.10
-    - MONGODB=3.6.2
+    - MONGODB=4.0.0
+    - MONGODB=3.6.6
+    - MONGODB=3.4.15
 
 sudo: false
 
@@ -39,4 +41,4 @@ script:
 
 matrix:
   allow_failures:
-    - rvm: 2.5
+    - rvm: ruby-head
diff --git a/README.md b/README.md
index aba0f0964..2c736a9dd 100644
--- a/README.md
+++ b/README.md
@@ -57,8 +57,8 @@ updates and notifications.
 
 The list of requirements to install Errbit are:
 
-* Ruby 2.3.x-2.4.x (>= 2.5.x not yet supported)
-* MongoDB 3.2.x-3.6.x (>= 4.0.x not yet supported)
+* Ruby >= 2.3.x
+* MongoDB 3.4.x-4.0.x
 
 Installation
 ------------