diff --git a/src/controllers/api/inventoryController.ts b/src/controllers/api/inventoryController.ts
index a26a73c5..97cc050b 100644
--- a/src/controllers/api/inventoryController.ts
+++ b/src/controllers/api/inventoryController.ts
@@ -340,7 +340,7 @@ export const getInventoryResponse = async (
 };
 
 const addString = (arr: string[], str: string): void => {
-    if (!arr.find(x => x == str)) {
+    if (arr.indexOf(str) == -1) {
         arr.push(str);
     }
 };
diff --git a/src/controllers/api/loginRewardsSelectionController.ts b/src/controllers/api/loginRewardsSelectionController.ts
index 4b6fc210..290a13f8 100644
--- a/src/controllers/api/loginRewardsSelectionController.ts
+++ b/src/controllers/api/loginRewardsSelectionController.ts
@@ -26,7 +26,7 @@ export const loginRewardsSelectionController: RequestHandler = async (req, res)
             StoreItemType: body.ChosenReward
         };
         inventoryChanges = (await handleStoreItemAcquisition(body.ChosenReward, inventory)).InventoryChanges;
-        if (!evergreenRewards.find(x => x == body.ChosenReward)) {
+        if (evergreenRewards.indexOf(body.ChosenReward) == -1) {
             inventory.LoginMilestoneRewards.push(body.ChosenReward);
         }
     } else {
diff --git a/src/controllers/api/nemesisController.ts b/src/controllers/api/nemesisController.ts
index 861e01ab..df8e1652 100644
--- a/src/controllers/api/nemesisController.ts
+++ b/src/controllers/api/nemesisController.ts
@@ -177,7 +177,7 @@ export const nemesisController: RequestHandler = async (req, res) => {
             weaponIdx = initialWeaponIdx;
             do {
                 const weapon = weapons[weaponIdx];
-                if (!body.target.DisallowedWeapons.find(x => x == weapon)) {
+                if (body.target.DisallowedWeapons.indexOf(weapon) == -1) {
                     break;
                 }
                 weaponIdx = (weaponIdx + 1) % weapons.length;
diff --git a/src/services/guildService.ts b/src/services/guildService.ts
index f1bb5ff9..0d8999aa 100644
--- a/src/services/guildService.ts
+++ b/src/services/guildService.ts
@@ -445,7 +445,7 @@ export const addGuildMemberShipDecoContribution = (guildMember: IGuildMemberData
 export const processDojoBuildMaterialsGathered = (guild: TGuildDatabaseDocument, build: IDojoBuild): void => {
     if (build.guildXpValue) {
         guild.ClaimedXP ??= [];
-        if (!guild.ClaimedXP.find(x => x == build.resultType)) {
+        if (guild.ClaimedXP.indexOf(build.resultType) == -1) {
             guild.ClaimedXP.push(build.resultType);
             guild.XP += build.guildXpValue;
         }
diff --git a/src/services/loginService.ts b/src/services/loginService.ts
index 41e33ad3..f2ae70ec 100644
--- a/src/services/loginService.ts
+++ b/src/services/loginService.ts
@@ -90,7 +90,7 @@ export const getAccountIdForRequest = async (req: Request): Promise<string> => {
 };
 
 export const isAdministrator = (account: TAccountDocument): boolean => {
-    return !!config.administratorNames?.find(x => x == account.DisplayName);
+    return config.administratorNames?.indexOf(account.DisplayName) != -1;
 };
 
 const platform_magics = [753, 639, 247, 37, 60];
diff --git a/src/services/missionInventoryUpdateService.ts b/src/services/missionInventoryUpdateService.ts
index 4a5150fe..e577a486 100644
--- a/src/services/missionInventoryUpdateService.ts
+++ b/src/services/missionInventoryUpdateService.ts
@@ -383,7 +383,7 @@ export const addMissionInventoryUpdates = async (
                     }
                     if (
                         inventory.LibraryActiveDailyTaskInfo &&
-                        inventory.LibraryActiveDailyTaskInfo.EnemyTypes.find(x => x == scan.EnemyType)
+                        inventory.LibraryActiveDailyTaskInfo.EnemyTypes.indexOf(scan.EnemyType) != -1
                     ) {
                         inventory.LibraryActiveDailyTaskInfo.Scans ??= 0;
                         inventory.LibraryActiveDailyTaskInfo.Scans += scan.Count;