diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5e1e6d4..6a5d9fd 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,8 +11,6 @@ jobs:
     - uses: actions/checkout@v4
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
-      with:
-        ruby-version: 3.3
     - name: Install dependencies
       run: bundle install
     - name: Run rubocop
@@ -39,7 +37,6 @@ jobs:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 3.3
         bundler-cache: true
     - name: build
       run: rake build:${{ matrix.os-arch }}
@@ -72,7 +69,6 @@ jobs:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 3.3
         bundler-cache: true
     - name: Install dependencies
       run: bundle install
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 11a6475..c568d55 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -23,7 +23,6 @@ jobs:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 3.3
         bundler-cache: true
     - name: Build assets
       run: rake build:assets
diff --git a/.rubocop.yml b/.rubocop.yml
index 465bdb0..3014347 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -2,10 +2,10 @@ require: rubocop-rspec
 
 AllCops:
   NewCops: enable
-  TargetRubyVersion: 3.3
   SuggestExtensions: false
   Exclude:
     - build/**/*
+    - mruby/**/*
 
 Lint/AssignmentInCondition:
   Enabled: false
diff --git a/.ruby-version b/.ruby-version
new file mode 100644
index 0000000..a0891f5
--- /dev/null
+++ b/.ruby-version
@@ -0,0 +1 @@
+3.3.4
diff --git a/Gemfile b/Gemfile
index 96863ae..7fb3db6 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,15 +1,15 @@
 source 'https://rubygems.org/'
 
+ruby file: '.ruby-version'
+
 gem 'rake'
 
 group 'test' do
   gem 'aruba', github: 'cucumber/aruba', branch: 'main'
+  gem 'ffi'
   gem 'parallel_tests'
   gem 'rspec'
   gem 'rspec-parameterized', '>= 1.0.0'
   gem 'rubocop'
   gem 'rubocop-rspec'
-
-  # fix: build error on windows
-  gem 'ffi', github: 'ffi/ffi', branch: 'master'
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index 62951cd..4c5a315 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -10,13 +10,6 @@ GIT
       rspec-expectations (~> 3.4)
       thor (~> 1.0)
 
-GIT
-  remote: https://github.com/ffi/ffi.git
-  revision: ecfb225096ae76ba2a5e8115f046bd0ac23095e6
-  branch: master
-  specs:
-    ffi (1.17.0)
-
 GEM
   remote: https://rubygems.org/
   specs:
@@ -54,6 +47,9 @@ GEM
     cucumber-tag-expressions (6.1.0)
     debug_inspector (1.2.0)
     diff-lcs (1.5.1)
+    ffi (1.17.0-arm64-darwin)
+    ffi (1.17.0-x64-mingw-ucrt)
+    ffi (1.17.0-x86_64-linux-gnu)
     json (2.7.2)
     language_server-protocol (3.17.0.3)
     mini_mime (1.1.5)
@@ -124,13 +120,13 @@ GEM
       parser (>= 3.3.0)
 
 PLATFORMS
-  arm64-darwin-22
+  arm64-darwin-23
   x64-mingw-ucrt
   x86_64-linux
 
 DEPENDENCIES
   aruba!
-  ffi!
+  ffi
   parallel_tests
   rake
   rspec
@@ -138,5 +134,8 @@ DEPENDENCIES
   rubocop
   rubocop-rspec
 
+RUBY VERSION
+   ruby 3.3.4p94
+
 BUNDLED WITH
-   2.5.3
+   2.5.11
diff --git a/mruby b/mruby
index 7c7ee5c..ac8846d 160000
--- a/mruby
+++ b/mruby
@@ -1 +1 @@
-Subproject commit 7c7ee5c244d48a8473d67825dcd2528c769706ba
+Subproject commit ac8846dbce403f2666303b309e020359ce7c0867
diff --git a/perf.data b/perf.data
deleted file mode 100644
index 46f3c89..0000000
Binary files a/perf.data and /dev/null differ