diff --git a/services/backtesting_service/src/dbn_repository.rs b/services/backtesting_service/src/dbn_repository.rs
index 9c6cda8f5..9d5367372 100644
--- a/services/backtesting_service/src/dbn_repository.rs
+++ b/services/backtesting_service/src/dbn_repository.rs
@@ -750,8 +750,8 @@ mod tests {
 
         let repo = DbnMarketDataRepository::new(file_mapping).await.unwrap();
 
-        let start = Utc.with_ymd_and_hms(2024, 1, 2, 0, 0, 0).expect("INVARIANT: Valid date/time parameters");
-        let end = Utc.with_ymd_and_hms(2024, 1, 2, 1, 0, 0).expect("INVARIANT: Valid date/time parameters");
+        let start = Utc.with_ymd_and_hms(2024, 1, 2, 0, 0, 0).unwrap();
+        let end = Utc.with_ymd_and_hms(2024, 1, 2, 1, 0, 0).unwrap();
 
         let symbols = vec!["ES.FUT".to_string()];
         let result = repo.load_by_time_range(&symbols, start, end).await;
diff --git a/services/ml_training_service/src/data_loader.rs b/services/ml_training_service/src/data_loader.rs
index b31f83d4b..dc7ea6f84 100644
--- a/services/ml_training_service/src/data_loader.rs
+++ b/services/ml_training_service/src/data_loader.rs
@@ -154,7 +154,7 @@ impl RiskMetricsCalculator {
             return -0.05; // Default: -5% if insufficient data
         }
 
-        let mut max_price = self.price_history.first().copied().unwrap_or(0.0);
+        let mut max_price = self.price_history.front().copied().unwrap_or(0.0);
         let mut max_drawdown = 0.0;
 
         for price in self.price_history.iter().skip(1) {