diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..ff83580
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,24 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v4
+
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: 3.2.2
+          bundler: 2.5.23
+          bundler-cache: true
+
+      - name: Run test suite
+        run: bundle exec rake
diff --git a/.ruby-version b/.ruby-version
new file mode 100644
index 0000000..a0891f5
--- /dev/null
+++ b/.ruby-version
@@ -0,0 +1 @@
+3.3.4
diff --git a/Gemfile b/Gemfile
index c896291..ffe885c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,4 @@
-source "http://rubygems.org"
+source "https://rubygems.org"
 
 gem 'rake'
 # Specify your gem's dependencies in omniauth-twitter.gemspec
diff --git a/Gemfile.lock b/Gemfile.lock
index 0402a9f..4fe372e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -6,14 +6,14 @@ PATH
       omniauth-oauth2 (~> 1.4)
 
 GEM
-  remote: http://rubygems.org/
+  remote: https://rubygems.org/
   specs:
-    addressable (2.8.0)
-      public_suffix (>= 2.0.2, < 5.0)
+    addressable (2.9.0)
+      public_suffix (>= 2.0.2, < 8.0)
     crack (0.4.2)
       safe_yaml (~> 1.0.0)
     diff-lcs (1.2.5)
-    docile (1.1.5)
+    docile (1.4.1)
     faraday (2.14.1)
       faraday-net_http (>= 2.0, < 3.5)
       json
@@ -21,7 +21,7 @@ GEM
     faraday-net_http (3.4.2)
       net-http (~> 0.5)
     hashie (5.0.0)
-    json (1.8.2)
+    json (2.19.3)
     jwt (2.7.0)
     logger (1.7.0)
     multi_json (1.15.0)
@@ -42,27 +42,34 @@ GEM
     omniauth-oauth2 (1.8.0)
       oauth2 (>= 1.4, < 3)
       omniauth (~> 2.0)
-    public_suffix (4.0.6)
+    public_suffix (7.0.5)
     rack (3.1.21)
     rack-protection (3.0.5)
       rack
     rack-test (0.6.3)
       rack (>= 1.0)
     rake (13.0.1)
-    rspec (2.99.0)
-      rspec-core (~> 2.99.0)
-      rspec-expectations (~> 2.99.0)
-      rspec-mocks (~> 2.99.0)
-    rspec-core (2.99.2)
-    rspec-expectations (2.99.2)
-      diff-lcs (>= 1.1.3, < 2.0)
-    rspec-mocks (2.99.3)
+    rexml (3.4.4)
+    rspec (3.13.0)
+      rspec-core (~> 3.13.0)
+      rspec-expectations (~> 3.13.0)
+      rspec-mocks (~> 3.13.0)
+    rspec-core (3.13.0)
+      rspec-support (~> 3.13.0)
+    rspec-expectations (3.13.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.13.0)
+    rspec-mocks (3.13.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.13.0)
+    rspec-support (3.13.1)
     safe_yaml (1.0.4)
-    simplecov (0.10.0)
-      docile (~> 1.1.0)
-      json (~> 1.8)
-      simplecov-html (~> 0.10.0)
-    simplecov-html (0.10.0)
+    simplecov (0.22.0)
+      docile (~> 1.1)
+      simplecov-html (~> 0.11)
+      simplecov_json_formatter (~> 0.1)
+    simplecov-html (0.13.2)
+    simplecov_json_formatter (0.1.4)
     snaky_hash (2.0.1)
       hashie
       version_gem (~> 1.1, >= 1.1.1)
@@ -79,8 +86,9 @@ DEPENDENCIES
   omniauth-bitly!
   rack-test
   rake
-  rspec (~> 2.7)
-  simplecov
+  rexml
+  rspec (~> 3.13)
+  simplecov (~> 0.22)
   webmock
 
 BUNDLED WITH
diff --git a/Rakefile b/Rakefile
index 7bb7c79..7c784fd 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,8 +1,10 @@
 require "bundler/gem_tasks"
-require 'rspec/core/rake_task'
+require "rake/testtask"
 
 desc "Run specs"
-RSpec::Core::RakeTask.new
+task :spec do
+  sh "bundle exec rspec spec"
+end
 
-desc 'Default: run specs.'
-task :default => :spec
+desc "Default: run specs."
+task default: :spec
diff --git a/omniauth-bitly.gemspec b/omniauth-bitly.gemspec
index b5b2954..97f99ec 100644
--- a/omniauth-bitly.gemspec
+++ b/omniauth-bitly.gemspec
@@ -20,8 +20,9 @@ Gem::Specification.new do |s|
 
   s.add_dependency 'multi_json', '~> 1.3'
   s.add_runtime_dependency 'omniauth-oauth2', '~> 1.4'
-  s.add_development_dependency 'rspec', '~> 2.7'
+  s.add_development_dependency 'rspec', '~> 3.13'
   s.add_development_dependency 'rack-test'
-  s.add_development_dependency 'simplecov'
+  s.add_development_dependency 'rexml'
+  s.add_development_dependency 'simplecov', '~> 0.22'
   s.add_development_dependency 'webmock'
 end
diff --git a/spec/omniauth/strategies/bitly_spec.rb b/spec/omniauth/strategies/bitly_spec.rb
index 2d3b20f..90d9365 100644
--- a/spec/omniauth/strategies/bitly_spec.rb
+++ b/spec/omniauth/strategies/bitly_spec.rb
@@ -15,7 +15,7 @@
     end
 
     it 'should have correct authorize url' do
-      subject.options.client_options.authorize_path.should eq('/oauth/authorize')
+      subject.options.client_options.authorize_url.should eq('https://bitly.com/oauth/authorize')
     end
   end
 end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 1447b9a..b1dc3f1 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -14,3 +14,8 @@
   config.extend  OmniAuth::Test::StrategyMacros, :type => :strategy
 end
 
+RSpec.configure do |config|
+  config.expect_with :rspec do |expectations|
+    expectations.syntax = :should
+  end
+end