diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a320273..fcb4ab5 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -3,6 +3,7 @@ name: CI
 on:
   - push
   - pull_request
+  - workflow_dispatch
 
 jobs:
   test:
@@ -13,10 +14,11 @@ jobs:
         ruby:
           - 2.6
           - 2.7
-          - 3.0
+          - '3.0'
           - 3.1
           - 3.2
           - 3.3
+          - 3.4
           - head
     steps:
       - name: Checkout code
@@ -30,4 +32,3 @@ jobs:
         run: bundle exec standardrb
       - name: test
         run: bundle exec rake test
-        continue-on-error: ${{ matrix.ruby == 'head' }}
diff --git a/Gemfile b/Gemfile
index b27d851..a796760 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,3 +4,7 @@ gem "sys-proctable"
 gemspec
 
 gem "standard"
+
+if RUBY_VERSION >= "3.5.0"
+  gem "ostruct"
+end