diff --git a/config/application.rb b/config/application.rb
index 5aca74fd1c6..59819679474 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -112,6 +112,8 @@ module Mastodon
       end
     end
 
+    config.x.mastodon = config_for(:mastodon)
+
     config.to_prepare do
       Doorkeeper::AuthorizationsController.layout 'modal'
       Doorkeeper::AuthorizedApplicationsController.layout 'admin'
diff --git a/config/mastodon.yml b/config/mastodon.yml
new file mode 100644
index 00000000000..94a71a5f105
--- /dev/null
+++ b/config/mastodon.yml
@@ -0,0 +1,8 @@
+shared:
+  source:
+    base_url: <%= ENV.fetch('SOURCE_BASE_URL', nil) %>
+    repository: <%= ENV.fetch('GITHUB_REPOSITORY', 'mastodon/mastodon') %>
+    tag: <%= ENV.fetch('SOURCE_TAG', nil) %>
+  version:
+    metadata: <%= ENV.fetch('MASTODON_VERSION_METADATA', nil) %>
+    prerelease: <%= ENV.fetch('MASTODON_VERSION_PRERELEASE', nil) %>
diff --git a/lib/mastodon/version.rb b/lib/mastodon/version.rb
index 96ad4092819..708a62e927f 100644
--- a/lib/mastodon/version.rb
+++ b/lib/mastodon/version.rb
@@ -21,11 +21,11 @@ module Mastodon
     end
 
     def prerelease
-      ENV['MASTODON_VERSION_PRERELEASE'].presence || default_prerelease
+      configuration.version[:prerelease] || default_prerelease
     end
 
     def build_metadata
-      ENV.fetch('MASTODON_VERSION_METADATA', nil)
+      configuration.version[:metadata]
     end
 
     def to_a
@@ -44,16 +44,16 @@ module Mastodon
     end
 
     def repository
-      ENV.fetch('GITHUB_REPOSITORY', 'mastodon/mastodon')
+      configuration.source[:repository]
     end
 
     def source_base_url
-      ENV.fetch('SOURCE_BASE_URL', "https://github.com/#{repository}")
+      configuration.source[:base_url] || "https://github.com/#{repository}"
     end
 
     # specify git tag or commit hash here
     def source_tag
-      ENV.fetch('SOURCE_TAG', nil)
+      configuration.source[:tag]
     end
 
     def source_url
@@ -67,5 +67,9 @@ module Mastodon
     def user_agent
       @user_agent ||= "#{HTTP::Request::USER_AGENT} (Mastodon/#{Version}; +http#{Rails.configuration.x.use_https ? 's' : ''}://#{Rails.configuration.x.web_domain}/)"
     end
+
+    def configuration
+      Rails.configuration.x.mastodon
+    end
   end
 end
diff --git a/spec/presenters/instance_presenter_spec.rb b/spec/presenters/instance_presenter_spec.rb
index 516c7e9896a..416d78734dd 100644
--- a/spec/presenters/instance_presenter_spec.rb
+++ b/spec/presenters/instance_presenter_spec.rb
@@ -65,11 +65,12 @@ describe InstancePresenter do
   end
 
   describe '#source_url' do
-    context 'with the GITHUB_REPOSITORY env variable set' do
+    context 'with the github repository configured' do
       around do |example|
-        ClimateControl.modify GITHUB_REPOSITORY: 'other/repo' do
-          example.run
-        end
+        original = Rails.configuration.x.mastodon.source[:repository]
+        Rails.configuration.x.mastodon.source[:repository] = 'other/repo'
+        example.run
+        Rails.configuration.x.mastodon.source[:repository] = original
       end
 
       it 'uses the env variable to build a repo URL' do
@@ -77,13 +78,7 @@ describe InstancePresenter do
       end
     end
 
-    context 'without the GITHUB_REPOSITORY env variable set' do
-      around do |example|
-        ClimateControl.modify GITHUB_REPOSITORY: nil do
-          example.run
-        end
-      end
-
+    context 'without the github repository configured' do
       it 'defaults to the core mastodon repo URL' do
         expect(instance_presenter.source_url).to eq('https://github.com/mastodon/mastodon')
       end