diff --git a/Gemfile b/Gemfile
index 04958167..7dc9c22b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,4 @@
-source 'https://rubygems.org'
+source 'https://gem.coop'
 git_source(:github){ |repo_name| "https://github.com/#{repo_name}.git" }
 
 gem 'rails', '~> 8'
diff --git a/Gemfile.lock b/Gemfile.lock
index 581235dd..eeb95173 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -5,7 +5,7 @@ GIT
     gravatar_image_tag (1.2.0)
 
 GEM
-  remote: https://rubygems.org/
+  remote: https://gem.coop/
   specs:
     SyslogLogger (2.0)
     action_text-trix (2.1.16)
@@ -105,7 +105,7 @@ GEM
     connection_pool (3.0.2)
     crass (1.0.6)
     date (3.5.1)
-    docile (1.1.5)
+    docile (1.4.1)
     drb (2.2.3)
     erb (6.0.1)
     erubi (1.13.1)
@@ -175,6 +175,7 @@ GEM
     minitest (6.0.1)
       prism (~> 1.5)
     msgpack (1.8.0)
+    multi_json (1.19.1)
     net-http (0.9.1)
       uri (>= 0.11.1)
     net-imap (0.6.2)
@@ -271,11 +272,10 @@ GEM
     simple_form (5.4.1)
       actionpack (>= 7.0)
       activemodel (>= 7.0)
-    simplecov (0.13.0)
-      docile (~> 1.1.0)
-      json (>= 1.8, < 3)
-      simplecov-html (~> 0.10.0)
-    simplecov-html (0.10.2)
+    simplecov (0.7.1)
+      multi_json (~> 1.0)
+      simplecov-html (~> 0.7.1)
+    simplecov-html (0.7.1)
     spring (4.4.0)
     sprockets (4.2.2)
       concurrent-ruby (~> 1.0)