diff --git a/.github/workflows/ruby_h_to_go.yml b/.github/workflows/ruby_h_to_go.yml
index 1838ad4f..29d530c0 100644
--- a/.github/workflows/ruby_h_to_go.yml
+++ b/.github/workflows/ruby_h_to_go.yml
@@ -61,8 +61,6 @@ jobs:
       - run: sudo apt-get update
       - run: sudo apt-get install -y universal-ctags
 
-      - run: go install golang.org/x/tools/cmd/goimports@latest
-
       - run: bundle exec rspec
 
       - name: Slack Notification (not success)
diff --git a/_tools/ruby_h_to_go/README.md b/_tools/ruby_h_to_go/README.md
index b5860737..998e00d5 100644
--- a/_tools/ruby_h_to_go/README.md
+++ b/_tools/ruby_h_to_go/README.md
@@ -7,8 +7,6 @@ Convert Ruby C function definition in `ruby.h` to Go source and dump to `dist/`.
 * ctags
   * macOS: `brew install universal-ctags`
   * Ubuntu: `apt-get install -y universal-ctags`
-* [goimports](https://pkg.go.dev/golang.org/x/tools/cmd/goimports)
-  * `go install golang.org/x/tools/cmd/goimports@latest`
 
 ## Usage
 Output binding to [/ruby/](/ruby/) using Ruby available in current context **(recommended)**
diff --git a/_tools/ruby_h_to_go/lib/ruby_h_to_go/cli.rb b/_tools/ruby_h_to_go/lib/ruby_h_to_go/cli.rb
index 430b120d..8210849e 100644
--- a/_tools/ruby_h_to_go/lib/ruby_h_to_go/cli.rb
+++ b/_tools/ruby_h_to_go/lib/ruby_h_to_go/cli.rb
@@ -119,11 +119,8 @@ def copy_go_files
     end
 
     def remove_unused_imports
-      ret = system("which goimports")
-      raise "goimports isn't installed. Run `go install golang.org/x/tools/cmd/goimports@latest`" unless ret
-
       Dir.chdir(dist_dir) do
-        system("goimports -w *.go", exception: true)
+        system("go tool goimports -w *.go", exception: true)
       end
     end
 
diff --git a/_tools/ruby_h_to_go/spec/ruby_h_to_go/cli_spec.rb b/_tools/ruby_h_to_go/spec/ruby_h_to_go/cli_spec.rb
index ccf0f8fa..e1c27f1d 100644
--- a/_tools/ruby_h_to_go/spec/ruby_h_to_go/cli_spec.rb
+++ b/_tools/ruby_h_to_go/spec/ruby_h_to_go/cli_spec.rb
@@ -19,6 +19,10 @@
 
     before do
       FileUtils.cp(File.join(project_root_dir, "go.mod"), temp_dir)
+
+      Dir.chdir(temp_dir) do
+        system("go mod tidy", exception: true)
+      end
     end
 
     it { expect { subject }.not_to raise_error }
diff --git a/go.mod b/go.mod
index 1fd39fc1..1249e00e 100644
--- a/go.mod
+++ b/go.mod
@@ -2,10 +2,19 @@ module github.com/ruby-go-gem/go-gem-wrapper
 
 go 1.24
 
+toolchain go1.25.0
+
 require github.com/stretchr/testify v1.11.1
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
+	golang.org/x/mod v0.33.0 // indirect
+	golang.org/x/sync v0.19.0 // indirect
+	golang.org/x/sys v0.41.0 // indirect
+	golang.org/x/telemetry v0.0.0-20260209163413-e7419c687ee4 // indirect
+	golang.org/x/tools v0.42.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
+
+tool golang.org/x/tools/cmd/goimports
diff --git a/go.sum b/go.sum
index c4c1710c..b1362161 100644
--- a/go.sum
+++ b/go.sum
@@ -1,9 +1,21 @@
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+golang.org/x/mod v0.33.0 h1:tHFzIWbBifEmbwtGz65eaWyGiGZatSrT9prnU8DbVL8=
+golang.org/x/mod v0.33.0/go.mod h1:swjeQEj+6r7fODbD2cqrnje9PnziFuw4bmLbBZFrQ5w=
+golang.org/x/sync v0.19.0 h1:vV+1eWNmZ5geRlYjzm2adRgW2/mcpevXNg50YZtPCE4=
+golang.org/x/sync v0.19.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
+golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
+golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+golang.org/x/telemetry v0.0.0-20260209163413-e7419c687ee4 h1:bTLqdHv7xrGlFbvf5/TXNxy/iUwwdkjhqQTJDjW7aj0=
+golang.org/x/telemetry v0.0.0-20260209163413-e7419c687ee4/go.mod h1:g5NllXBEermZrmR51cJDQxmJUHUOfRAaNyWBM+R+548=
+golang.org/x/tools v0.42.0 h1:uNgphsn75Tdz5Ji2q36v/nsFSfR/9BRFvqhGBaJGd5k=
+golang.org/x/tools v0.42.0/go.mod h1:Ma6lCIwGZvHK6XtgbswSoWroEkhugApmsXyrUmBhfr0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=