diff --git a/lib/install/helpers.rb b/lib/install/helpers.rb
index cf5b612..011e21d 100644
--- a/lib/install/helpers.rb
+++ b/lib/install/helpers.rb
@@ -15,8 +15,7 @@ def bundler_x_cmd
 
   def using_bun?
     tool_exists?('bun') && (File.exist?('bun.lockb') || 
-                            File.exist?('bun.lock') ||       
-                            File.exist?('yarn.lock'))
+                            File.exist?('bun.lock'))
   end
 
   def tool_exists?(tool)
diff --git a/lib/tasks/cssbundling/build.rake b/lib/tasks/cssbundling/build.rake
index ddce5ab..a8cefde 100644
--- a/lib/tasks/cssbundling/build.rake
+++ b/lib/tasks/cssbundling/build.rake
@@ -22,7 +22,7 @@ module Cssbundling
     extend self
 
     LOCK_FILES = {
-      bun: %w[bun.lockb bun.lock yarn.lock],
+      bun: %w[bun.lockb bun.lock],
       yarn: %w[yarn.lock],
       pnpm: %w[pnpm-lock.yaml],
       npm: %w[package-lock.json]