diff --git a/Gemfile b/Gemfile
index 8eb1284..85841c2 100644
--- a/Gemfile
+++ b/Gemfile
@@ -26,5 +26,5 @@ group :development, :test do
   gem 'minitest'
   gem 'mocha'
   gem 'ostruct'
-  gem 'simplecov', '0.17.1', require: false # CC last supported v0.17
+  gem 'simplecov', '0.22.0', require: false # CC last supported v0.17
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index 86c374c..1b16ddc 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -33,7 +33,7 @@ GEM
     eventmachine (1.2.7)
     i18n (1.14.7)
       concurrent-ruby (~> 1.0)
-    json (2.15.2)
+    json (2.16.0)
     language_server-protocol (3.17.0.5)
     lint_roller (1.1.0)
     logger (1.7.0)
@@ -75,11 +75,12 @@ GEM
     ruby-progressbar (1.13.0)
     ruby2_keywords (0.0.5)
     securerandom (0.4.1)
-    simplecov (0.17.1)
+    simplecov (0.22.0)
       docile (~> 1.1)
-      json (>= 1.8, < 3)
-      simplecov-html (~> 0.10.0)
-    simplecov-html (0.10.2)
+      simplecov-html (~> 0.11)
+      simplecov_json_formatter (~> 0.1)
+    simplecov-html (0.13.2)
+    simplecov_json_formatter (0.1.4)
     simpleidn (0.2.3)
     timeout (0.4.3)
     tzinfo (2.0.6)
@@ -104,7 +105,7 @@ DEPENDENCIES
   pg (~> 1.6.0)
   pry (~> 0.15.0)
   rubocop
-  simplecov (= 0.17.1)
+  simplecov (= 0.22.0)
   simpleidn (~> 0.2.1)
 
 RUBY VERSION