diff --git a/lib/modulesync/source_code.rb b/lib/modulesync/source_code.rb
index 2e93be6b..8e0c5c8a 100644
--- a/lib/modulesync/source_code.rb
+++ b/lib/modulesync/source_code.rb
@@ -45,7 +45,9 @@ def working_directory
     end
 
     def open_pull_request
-      git_service = GitService.instantiate type: git_service_type, options: @options[git_service_type]
+      git_service_options = @options[git_service_type] || {}
+      git_service_options[:base_url] = git_service_api_endpoint
+      git_service = GitService.instantiate type: git_service_type, options: git_service_options
       git_service.open_pull_request(
         repo_path: repository_path,
         namespace: repository_namespace,
@@ -62,6 +64,10 @@ def git_service_type
       @git_service_type ||= guess_git_service_type
     end
 
+    def git_service_api_endpoint
+      @git_service_api_endpoint ||= @options.dig(git_service_type, 'base_url') || guess_git_service_api_endpoint
+    end
+
     private
 
     def _repository_remote
@@ -76,5 +82,13 @@ def guess_git_service_type
       return :gitlab if repository_remote.include? 'gitlab'
       :unknown
     end
+
+    def guess_git_service_api_endpoint
+      return unless git_service_type == :gitlab
+
+      pattern = /^git@(.*):(.*).git$/
+      return nil unless repository_remote.match?(pattern)
+      repository_remote.sub(pattern, 'https://\1/api/v4')
+    end
   end
 end