diff --git a/npm_install.py b/npm_install.py
index 7cff2bb..06e879f 100644
--- a/npm_install.py
+++ b/npm_install.py
@@ -2142,6 +2142,10 @@ def _build_frontend(src_frontend: Path, dest_frontend: Path):
             step_msg = f"Reinstalling Yarn 4.x (attempt {retry_count + 1}/{max_retries + 1})"
         
         with step(step_msg):
+            # Change CWD to /tmp to avoid workspace/package.json issues
+            original_cwd = os.getcwd()
+            os.chdir("/tmp")
+            
             # Cleanup on retry
             if retry_count > 0:
                 _cleanup_yarn_artifacts()
@@ -2199,10 +2203,11 @@ def _build_frontend(src_frontend: Path, dest_frontend: Path):
                         if shutil.which("yarn"):
                                 major = _get_yarn_major_version(["yarn"])
                                 
-                                if major and major >= 4:
-                                    if DEBUG:
-                                        print(f"   ✓ Yarn {major}.x installed via corepack")
-                                    return True
+                        if major and major >= 4:
+                            if DEBUG:
+                                print(f"   ✓ Yarn {major}.x installed via corepack")
+                            os.chdir(original_cwd)
+                            return True
                 except Exception as e:
                     if DEBUG:
                         print(f"   ⚠ Corepack method failed: {e}")
@@ -2245,7 +2250,8 @@ def _build_frontend(src_frontend: Path, dest_frontend: Path):
                     
                     if major and major >= 4:
                         if DEBUG:
-                            print(f"   ✓ Yarn {major}.x installed via @yarnpkg/cli")
+                            print(f"   ✓ Yarn {major}.x installed via 'yarn set version'")
+                        os.chdir(original_cwd)
                         return True
             except Exception as e:
                 if DEBUG:
@@ -2297,6 +2303,7 @@ def _build_frontend(src_frontend: Path, dest_frontend: Path):
                     if DEBUG:
                         print(f"   ⚠ 'yarn set version' failed: {e}")
             
+            os.chdir(original_cwd)
             return False
 
     # Main logic: Find or install Yarn 4.x