diff --git a/swh/lister/core/lister_base.py b/swh/lister/core/lister_base.py
--- a/swh/lister/core/lister_base.py
+++ b/swh/lister/core/lister_base.py
@@ -234,7 +234,7 @@
 
     @property
     def CONFIG_BASE_FILENAME(self):  # noqa: N802
-        return 'lister-%s' % self.LISTER_NAME
+        return 'lister_%s' % self.LISTER_NAME
 
     @property
     def ADDITIONAL_CONFIG(self):  # noqa: N802
diff --git a/swh/lister/npm/lister.py b/swh/lister/npm/lister.py
--- a/swh/lister/npm/lister.py
+++ b/swh/lister/npm/lister.py
@@ -117,7 +117,7 @@
 
     @property
     def CONFIG_BASE_FILENAME(self):  # noqa: N802
-        return 'lister-npm-incremental'
+        return 'lister_npm_incremental'
 
     def get_next_target_from_response(self, response):
         """(Override) Get next npm package name to continue the listing