diff --git a/modules/services/oberon.nix b/modules/services/oberon.nix
index 188568d..1abf602 100644
--- a/modules/services/oberon.nix
+++ b/modules/services/oberon.nix
@@ -65,6 +65,8 @@ in
         "RELAY_URLS=${relayUrl}"
         "CDN_URL=${cdnUrl}"
         "CDN_APP_NAME=xfay"
+        # Feature flags. Credits stay off (defaults false); PDF fax is entitlement-gated.
+        "FAX_PDF_ENABLED=true"
         # Abuse controls (M4) — start conservative; empty prefix list = allow all.
         "ALLOWED_DESTINATION_PREFIXES=+1"
         "MAX_FAXES_PER_PUBKEY_PER_DAY=20"