diff --git a/.github/workflows/rubocop.yml b/.github/workflows/rubocop.yml
index 73ae6de60..47815fcff 100644
--- a/.github/workflows/rubocop.yml
+++ b/.github/workflows/rubocop.yml
@@ -23,14 +23,14 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu ]
-        ruby: [ 2.4, 2.5, 2.6, 2.7, head ]
+        ruby: [ 2.4, 2.5, 2.6, 2.7, '3.0', head ]
         coverage: [ null ]
         modern: [ null ]
         title: [ null ]
         include:
           - { os: windows, ruby: mingw }
           - { ruby: 2.4, os: ubuntu, coverage: true, title: 'Coverage' }
-          - { ruby: 2.7, os: ubuntu, modern: true, title: 'Specs "modern"' }
+          - { ruby: '3.0', os: ubuntu, modern: true, title: 'Specs "modern"' }
           - { ruby: jruby, os: ubuntu }
           # jruby-head disabled because of: https://github.com/jruby/jruby/issues/6416
           # - { ruby: jruby-head, os: ubuntu }
@@ -84,6 +84,8 @@ jobs:
         ruby: [ 2.4, 2.7 ]
         rubocop: [ 'v0.92.0', master ]
         internal_investigation: [ null ]
+        include:
+          - { rubocop: master, ruby: '3.0', os: ubuntu }
     steps:
       - name: checkout
         uses: actions/checkout@v2
@@ -115,7 +117,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu ]
-        ruby: [ 2.7 ]
+        ruby: [ 3.0 ]
         rubocop: [ master ]
     steps:
       - name: checkout
diff --git a/.mergify.yml b/.mergify.yml
index bedd57ee8..52c43d5c1 100644
--- a/.mergify.yml
+++ b/.mergify.yml
@@ -12,10 +12,11 @@ pull_request_rules:
       - 'status-success=Specs | 2.5'
       - 'status-success=Specs | 2.6'
       - 'status-success=Specs | 2.7'
+      - 'status-success=Specs | 3.0'
       - 'status-success=Specs | head'
       - 'status-success=Specs | mingw'
       - 'status-success=Coverage | 2.4'
-      - 'status-success=Specs "modern" | 2.7'
+      - 'status-success=Specs "modern" | 3.0'
       - 'status-success=Specs | jruby'
       - 'status-success=Specs | truffleruby'
       - 'status-success=Specs | truffleruby-head'
@@ -23,7 +24,8 @@ pull_request_rules:
       - 'status-success=Main Gem Specs | RuboCop: master | 2.4'
       - 'status-success=Main Gem Specs | RuboCop: v0.92.0 | 2.7'
       - 'status-success=Main Gem Specs | RuboCop: master | 2.7'
-      - 'status-success=Coding Style | 2.7'
+      - 'status-success=Main Gem Specs | RuboCop: master | 3.0'
+      - 'status-success=Coding Style | 3.0'
 
   - name: delete head branch after auto-merge
     conditions: