diff --git a/adapter_api.py b/adapter_api.py
index 1573eda..9bed061 100644
--- a/adapter_api.py
+++ b/adapter_api.py
@@ -187,14 +187,40 @@ def retry_dead_letter():
 
 # ── Public file serving ───────────────────────────────────────
 # Serves deployment artifacts for KoreNet/Corné to pull directly
-# No auth required — public read-only static files
+# Basic auth gated — credentials in environment variables
+
+def check_public_auth():
+    """Basic auth for public file serving."""
+    from flask import request, Response
+    import os, hmac, hashlib
+    auth = request.authorization
+    expected_user = os.environ.get('PUBLIC_USER', 'korenet')
+    expected_pass = os.environ.get('PUBLIC_PASS', '')
+    if not expected_pass:
+        return True  # No password configured — open access
+    if not auth:
+        return False
+    # Constant-time comparison
+    user_ok = hmac.compare_digest(auth.username.encode(), expected_user.encode())
+    pass_ok = hmac.compare_digest(auth.password.encode(), expected_pass.encode())
+    return user_ok and pass_ok
+
+def auth_required():
+    from flask import Response
+    return Response(
+        'Authentication required.',
+        401,
+        {'WWW-Authenticate': 'Basic realm="VZ Public Files"'}
+    )
 
 PUBLIC_DIR = os.path.join(os.path.dirname(__file__), 'public')
 os.makedirs(PUBLIC_DIR, exist_ok=True)
 
 @app.route('/public/<path:filename>')
 def serve_public(filename):
-    """Serve public deployment files."""
+    """Serve public deployment files — basic auth required."""
+    if not check_public_auth():
+        return auth_required()
     import re
     # Sanitise path — no directory traversal
     if '..' in filename or filename.startswith('/'):
@@ -218,7 +244,9 @@ def serve_public(filename):
 
 @app.route('/public')
 def list_public():
-    """List available public files."""
+    """List available public files — basic auth required."""
+    if not check_public_auth():
+        return auth_required()
     files = []
     if os.path.exists(PUBLIC_DIR):
         for f in sorted(os.listdir(PUBLIC_DIR)):