diff --git a/bascule-gateway/src/config.rs b/bascule-gateway/src/config.rs
index 9832ce8..0be859d 100644
--- a/bascule-gateway/src/config.rs
+++ b/bascule-gateway/src/config.rs
@@ -121,6 +121,7 @@ impl BasculeConfig {
         let config = config::Config::builder()
             .add_source(
                 config::Environment::with_prefix("BASCULE")
+                    .prefix_separator("_")
                     .separator("__")
                     .try_parsing(true),
             )
diff --git a/bascule-gateway/src/main.rs b/bascule-gateway/src/main.rs
index cbeba75..468ac7e 100644
--- a/bascule-gateway/src/main.rs
+++ b/bascule-gateway/src/main.rs
@@ -69,8 +69,8 @@ spec:
     fidelity: always_notarize
     notarize: []
     logOnly: []
-    sampled: []
-    sampleRate: 1
+    # sampled omitted — Option<SampledConfig> default None (struct shape:
+    # {events: [...], sample_rate: N}), `sampled: []` would mis-parse.
   reconciliation:
     defaultWindow: "24h"
     onExpiry: alert