diff --git a/backend/src/main/java/com/printcalculator/controller/OptionsController.java b/backend/src/main/java/com/printcalculator/controller/OptionsController.java
index 3b2295b..e187422 100644
--- a/backend/src/main/java/com/printcalculator/controller/OptionsController.java
+++ b/backend/src/main/java/com/printcalculator/controller/OptionsController.java
@@ -16,6 +16,7 @@ import com.printcalculator.repository.NozzleOptionRepository;
 import com.printcalculator.repository.PrinterMachineRepository;
 import com.printcalculator.service.OrcaProfileResolver;
 import org.springframework.http.ResponseEntity;
+import org.springframework.transaction.annotation.Transactional;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
@@ -54,13 +55,13 @@ public class OptionsController {
     }
 
     @GetMapping("/api/calculator/options")
+    @Transactional(readOnly = true)
     public ResponseEntity<OptionsResponse> getOptions(
             @RequestParam(value = "printerMachineId", required = false) Long printerMachineId,
             @RequestParam(value = "nozzleDiameter", required = false) Double nozzleDiameter
     ) {
         List<FilamentMaterialType> types = materialRepo.findAll();
-        List<FilamentVariant> allVariants = variantRepo.findAll().stream()
-                .filter(v -> Boolean.TRUE.equals(v.getIsActive()))
+        List<FilamentVariant> allVariants = variantRepo.findByIsActiveTrue().stream()
                 .sorted(Comparator
                         .comparing((FilamentVariant v) -> safeMaterialCode(v.getFilamentMaterialType()), String.CASE_INSENSITIVE_ORDER)
                         .thenComparing(v -> safeString(v.getVariantDisplayName()), String.CASE_INSENSITIVE_ORDER))
diff --git a/backend/src/main/java/com/printcalculator/repository/FilamentVariantRepository.java b/backend/src/main/java/com/printcalculator/repository/FilamentVariantRepository.java
index 43b9e73..bd70537 100644
--- a/backend/src/main/java/com/printcalculator/repository/FilamentVariantRepository.java
+++ b/backend/src/main/java/com/printcalculator/repository/FilamentVariantRepository.java
@@ -2,11 +2,16 @@ package com.printcalculator.repository;
 
 import com.printcalculator.entity.FilamentVariant;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.EntityGraph;
 
 import com.printcalculator.entity.FilamentMaterialType;
+import java.util.List;
 import java.util.Optional;
 
 public interface FilamentVariantRepository extends JpaRepository<FilamentVariant, Long> {
+    @EntityGraph(attributePaths = {"filamentMaterialType"})
+    List<FilamentVariant> findByIsActiveTrue();
+
     // We try to match by color name if possible, or get first active
     Optional<FilamentVariant> findByFilamentMaterialTypeAndColorName(FilamentMaterialType type, String colorName);
     Optional<FilamentVariant> findByFilamentMaterialTypeAndVariantDisplayName(FilamentMaterialType type, String variantDisplayName);
diff --git a/backend/src/main/java/com/printcalculator/repository/MaterialOrcaProfileMapRepository.java b/backend/src/main/java/com/printcalculator/repository/MaterialOrcaProfileMapRepository.java
index 0c2e61c..30c7d35 100644
--- a/backend/src/main/java/com/printcalculator/repository/MaterialOrcaProfileMapRepository.java
+++ b/backend/src/main/java/com/printcalculator/repository/MaterialOrcaProfileMapRepository.java
@@ -3,6 +3,7 @@ package com.printcalculator.repository;
 import com.printcalculator.entity.FilamentMaterialType;
 import com.printcalculator.entity.MaterialOrcaProfileMap;
 import com.printcalculator.entity.PrinterMachineProfile;
+import org.springframework.data.jpa.repository.EntityGraph;
 import org.springframework.data.jpa.repository.JpaRepository;
 
 import java.util.List;
@@ -14,5 +15,6 @@ public interface MaterialOrcaProfileMapRepository extends JpaRepository<Material
             FilamentMaterialType filamentMaterialType
     );
 
+    @EntityGraph(attributePaths = {"filamentMaterialType"})
     List<MaterialOrcaProfileMap> findByPrinterMachineProfileAndIsActiveTrue(PrinterMachineProfile printerMachineProfile);
 }