diff --git a/diaspora_federation-json_schema.gemspec b/diaspora_federation-json_schema.gemspec
index f2842cf..679fd51 100644
--- a/diaspora_federation-json_schema.gemspec
+++ b/diaspora_federation-json_schema.gemspec
@@ -16,8 +16,11 @@ Gem::Specification.new do |s|
   s.description = "This gem provides JSON schemas (currently one schema) for "\
                   "validating JSON serialized federation objects."
   s.license     = "AGPL-3.0"
+  s.metadata    = {
+    "rubygems_mfa_required" => "true"
+  }
 
-  s.files       = Dir["lib/diaspora_federation/schemas.rb", "lib/diaspora_federation/schemas/*.json"]
+  s.files = Dir["lib/diaspora_federation/schemas.rb", "lib/diaspora_federation/schemas/*.json"]
 
   s.required_ruby_version = ">= 2.6"
 end
diff --git a/diaspora_federation-rails.gemspec b/diaspora_federation-rails.gemspec
index c22fa4d..2bd46aa 100644
--- a/diaspora_federation-rails.gemspec
+++ b/diaspora_federation-rails.gemspec
@@ -15,9 +15,12 @@ Gem::Specification.new do |s|
   s.summary     = "diaspora* federation rails engine"
   s.description = "A rails engine that adds the diaspora* federation protocol to a rails app"
   s.license     = "AGPL-3.0"
+  s.metadata    = {
+    "rubygems_mfa_required" => "true"
+  }
 
-  s.files       = Dir["app/**/*", "config/routes.rb", "config/initializers/*",
-                      "lib/diaspora_federation/{engine,rails}.rb", "LICENSE", "README.md", "Changelog.md"]
+  s.files = Dir["app/**/*", "config/routes.rb", "config/initializers/*",
+                "lib/diaspora_federation/{engine,rails}.rb", "LICENSE", "README.md", "Changelog.md"]
 
   s.required_ruby_version = ">= 2.6"
 
diff --git a/diaspora_federation-test.gemspec b/diaspora_federation-test.gemspec
index 0dfda9b..293b270 100644
--- a/diaspora_federation-test.gemspec
+++ b/diaspora_federation-test.gemspec
@@ -16,8 +16,11 @@ Gem::Specification.new do |s|
   s.description = "This gem provides some supplimentary code (factory definitions), that"\
                   "helps to build tests for users of the diaspora_federation gem."
   s.license     = "AGPL-3.0"
+  s.metadata    = {
+    "rubygems_mfa_required" => "true"
+  }
 
-  s.files       = Dir["lib/diaspora_federation/test.rb", "lib/diaspora_federation/test/*"]
+  s.files = Dir["lib/diaspora_federation/test.rb", "lib/diaspora_federation/test/*"]
 
   s.required_ruby_version = ">= 2.6"
 
diff --git a/diaspora_federation.gemspec b/diaspora_federation.gemspec
index c7ab2e9..8316dc0 100644
--- a/diaspora_federation.gemspec
+++ b/diaspora_federation.gemspec
@@ -17,12 +17,15 @@ Gem::Specification.new do |s|
                   "de-/encryption of Entities in the protocols used for communication " \
                   "among the various installations of Diaspora*"
   s.license     = "AGPL-3.0"
+  s.metadata    = {
+    "rubygems_mfa_required" => "true"
+  }
 
-  s.files       = Dir["lib/**/*", "LICENSE", "README.md", "Changelog.md"] -
-                    Dir["lib/diaspora_federation/{engine,rails,schemas,test}.rb",
-                        "lib/diaspora_federation/schemas/*",
-                        "lib/diaspora_federation/test/*",
-                        "lib/tasks/*.rake"]
+  s.files = Dir["lib/**/*", "LICENSE", "README.md", "Changelog.md"] -
+    Dir["lib/diaspora_federation/{engine,rails,schemas,test}.rb",
+        "lib/diaspora_federation/schemas/*",
+        "lib/diaspora_federation/test/*",
+        "lib/tasks/*.rake"]
 
   s.required_ruby_version = ">= 2.6"