diff --git a/Gemfile b/Gemfile
index 8ad0c31..9828362 100644
--- a/Gemfile
+++ b/Gemfile
@@ -11,6 +11,6 @@ gem 'rake', '~> 13.4'
 gem 'rubocop', '~> 1.89'
 gem 'rubocop-minitest', '~> 0.40.0'
 gem 'rubocop-rake', '~> 0.7.1'
-gem 'simplecov', '~> 1.0', require: false # test coverage; output written to coverage/
+gem 'simplecov', '~> 1.1', require: false # test coverage; output written to coverage/
 gem 'steep', '~> 2.0', require: false       # static type checking against sig/*.rbs
 gem 'yard', '~> 0.9'                        # API doc generation; deployed via GitHub Pages
diff --git a/Gemfile.lock b/Gemfile.lock
index c20ebd9..0fdf9ce 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -64,7 +64,7 @@ GEM
       rubocop (>= 1.72.1)
     ruby-progressbar (1.13.0)
     securerandom (0.4.1)
-    simplecov (1.0.3)
+    simplecov (1.1.1)
     steep (2.0.0)
       concurrent-ruby (>= 1.1.10)
       csv (>= 3.0.9)
@@ -102,7 +102,7 @@ DEPENDENCIES
   rubocop (~> 1.89)
   rubocop-minitest (~> 0.40.0)
   rubocop-rake (~> 0.7.1)
-  simplecov (~> 1.0)
+  simplecov (~> 1.1)
   steep (~> 2.0)
   yard (~> 0.9)