diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 51efd91..c0dc891 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -32,3 +32,18 @@ jobs:
           bundler-cache: true
       - name: Test
         run: bundle exec rake
+
+  qlty:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0
+      - uses: ruby/setup-ruby@13e7a03dc3ac6c3798f4570bfead2aed4d96abfb # v1.244.0
+        with:
+          ruby-version: '3.2'
+          bundler-cache: true
+      - name: Test
+        run: bundle exec rake
+      - uses: qltysh/qlty-action/coverage@a19242102d17e497f437d7466aa01b528537e899 # v2.2.0
+        with:
+          token: ${{secrets.QLTY_COVERAGE_TOKEN}}
+          files: ./coverage/coverage.json
diff --git a/Gemfile b/Gemfile
index a82e044..4e04196 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,3 +10,4 @@ gem "rake"
 gem "rspec", "~> 3.1"
 gem "rubocop", "~> 1.76.0"
 gem "simplecov", "!= 0.18.0", "!= 0.18.1", "!= 0.18.2", "!= 0.18.3", "!= 0.18.4", "!= 0.18.5", "!= 0.19.0", "!= 0.19.1"
+gem "simplecov_json_formatter"
diff --git a/README.md b/README.md
index 3d73255..3f062dc 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,8 @@
 
 [![Gem Version](https://badge.fury.io/rb/qiita-markdown.svg)](https://badge.fury.io/rb/qiita-markdown)
 [![Build Status](https://travis-ci.org/increments/qiita-markdown.svg)](https://travis-ci.org/increments/qiita-markdown)
+[![Maintainability](https://qlty.sh/gh/increments/projects/qiita-markdown/maintainability.svg)](https://qlty.sh/gh/increments/projects/qiita-markdown)
+[![Code Coverage](https://qlty.sh/gh/increments/projects/qiita-markdown/coverage.svg)](https://qlty.sh/gh/increments/projects/qiita-markdown)
 
 Qiita-specified markdown processor.
 
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 554dc73..dfe0bfd 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,6 +1,14 @@
 if ENV["CI"]
   require "simplecov"
-  SimpleCov.start
+  require "simplecov_json_formatter"
+  SimpleCov.start do
+    SimpleCov.formatters = [
+      SimpleCov::Formatter::JSONFormatter,
+      SimpleCov::Formatter::HTMLFormatter,
+    ]
+
+    add_filter "/spec/"
+  end
 end
 
 require "qiita-markdown"