diff --git a/backend/app/pypi_proxy.py b/backend/app/pypi_proxy.py
index 0b380c8..287426d 100644
--- a/backend/app/pypi_proxy.py
+++ b/backend/app/pypi_proxy.py
@@ -551,7 +551,8 @@ def _cache_dependency_background(
                 matches = re.findall(sdist_pattern, html, re.IGNORECASE)
 
             if not matches:
-                logger.warning(f"PyPI proxy: no downloadable files found for {dep_name}")
+                # Debug: log first 500 chars of HTML and the pattern we're looking for
+                logger.warning(f"PyPI proxy: no downloadable files found for {dep_name}. Pattern: {wheel_pattern}, HTML preview: {html[:500]}")
                 return
 
             # Get the last match (usually the latest version)