diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ac9ba1b26..1f092b36b 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -12,7 +12,8 @@ Try to write a test case and include it in your report (have a look at the
 [regression test suite](spec/regressions) if you need inspiration).
 
 1. Bundle with `bundle install`
-1. Run the unit test suite with `rake rspec`
+2. Compile native extension with `rake compile`
+3. Run the unit test suite with `rake rspec`
   * Using this rake task will install necessary ruby extensions as a prerequisite
   * For `bundle exec rspec` to be successful, run `bundle exec rake compile` once, beforehand
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 62622f396..be6154a01 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -3,6 +3,7 @@ PATH
   specs:
     cassandra-driver (3.2.5)
       ione (~> 1.2)
+      sorted_set
 
 GEM
   remote: https://rubygems.org/
@@ -40,9 +41,9 @@ GEM
     ffi (1.9.25)
     ffi (1.9.25-java)
     gherkin (3.2.0)
-    ione (1.2.4)
-    json (1.8.6)
-    json (1.8.6-java)
+    ione (1.2.5)
+    json (2.6.3)
+    json (2.6.3-java)
     lz4-ruby (0.3.3)
     lz4-ruby (0.3.3-java)
     minitest (4.7.5)
@@ -59,6 +60,7 @@ GEM
     rake (13.0.1)
     rake-compiler (0.9.5)
       rake
+    rbtree (0.4.6)
     rspec (3.9.0)
       rspec-core (~> 3.9.0)
       rspec-expectations (~> 3.9.0)
@@ -84,15 +86,20 @@ GEM
       ruby-progressbar (~> 1.7)
       unicode-display_width (~> 1.0, >= 1.0.1)
     ruby-progressbar (1.9.0)
-    simplecov (0.11.2)
-      docile (~> 1.1.0)
-      json (~> 1.8)
+    set (1.0.3)
+    simplecov (0.17.1)
+      docile (~> 1.1)
+      json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
     simplecov-html (0.10.0)
-    snappy (0.0.14)
-    snappy (0.0.14-java)
+    snappy (0.3.0)
+    snappy (0.3.0-java)
       snappy-jars (~> 1.1.0)
     snappy-jars (1.1.0.1.2-java)
+    sorted_set (1.0.3)
+      rbtree
+      set (~> 1.0)
+    sorted_set (1.0.3-java)
     thor (0.19.1)
     unicode-display_width (1.3.0)
     yard (0.9.20)
@@ -104,7 +111,7 @@ PLATFORMS
 DEPENDENCIES
   ansi
   aruba
-  bundler (~> 1.6)
+  bundler
   cassandra-driver!
   cliver
   cucumber
@@ -113,7 +120,7 @@ DEPENDENCIES
   minitest (< 5.0.0)
   os
   perftools.rb
-  rake (~> 13.0)
+  rake
   rake-compiler
   rspec
   rspec-collection_matchers
@@ -124,4 +131,4 @@ DEPENDENCIES
   yard
 
 BUNDLED WITH
-   1.17.3
+   2.4.14
diff --git a/cassandra-driver.gemspec b/cassandra-driver.gemspec
index bd2624b50..c0021403c 100644
--- a/cassandra-driver.gemspec
+++ b/cassandra-driver.gemspec
@@ -32,6 +32,8 @@ Gem::Specification.new do |s|
 
   s.add_runtime_dependency 'ione', '~> 1.2'
 
-  s.add_development_dependency 'bundler', '~> 1.6'
-  s.add_development_dependency 'rake', '~> 13.0'
+  s.add_dependency 'sorted_set'
+
+  s.add_development_dependency 'bundler'
+  s.add_development_dependency 'rake'
 end