diff --git a/src/controllers/api/getFriendsController.ts b/src/controllers/api/getFriendsController.ts
index c0ec7b33..292e107c 100644
--- a/src/controllers/api/getFriendsController.ts
+++ b/src/controllers/api/getFriendsController.ts
@@ -1,6 +1,6 @@
 import { Request, Response } from "express";
 
-const getFriendsController = (_request: Request, response: Response) => {
+const getFriendsController = (_request: Request, response: Response): void => {
     response.writeHead(200, {
         //Connection: "keep-alive",
         //"Content-Encoding": "gzip",
diff --git a/src/helpers/inventoryHelpers.ts b/src/helpers/inventoryHelpers.ts
index 9c254fbe..d85fc978 100644
--- a/src/helpers/inventoryHelpers.ts
+++ b/src/helpers/inventoryHelpers.ts
@@ -1,4 +1,4 @@
-import { IOid } from "@/src/types/commonTypes";
+import { IMongoDate, IOid } from "@/src/types/commonTypes";
 import { IInventoryResponse } from "@/src/types/inventoryTypes/inventoryTypes";
 import { Types } from "mongoose";
 
@@ -9,10 +9,10 @@ export const toInventoryResponse = (inventoryDatabase: { accountOwnerId: Types.O
     return inventoryResponse as unknown as IInventoryResponse;
 };
 
-export const toOid = (objectId: Types.ObjectId) => {
+export const toOid = (objectId: Types.ObjectId): IOid => {
     return { $oid: objectId.toString() } satisfies IOid;
 };
 
-export const toMongoDate = (date: Date) => {
+export const toMongoDate = (date: Date): IMongoDate => {
     return { $date: { $numberLong: date.getTime().toString() } };
 };
diff --git a/src/helpers/purchaseHelpers.ts b/src/helpers/purchaseHelpers.ts
index 2b208221..e3f9b5be 100644
--- a/src/helpers/purchaseHelpers.ts
+++ b/src/helpers/purchaseHelpers.ts
@@ -43,7 +43,7 @@ export const isSlotPurchaseName = (slotPurchaseName: string): slotPurchaseName i
     return slotPurchaseName in slotPurchaseNameToSlotName;
 };
 
-export const parseSlotPurchaseName = (slotPurchaseName: string) => {
+export const parseSlotPurchaseName = (slotPurchaseName: string): SlotPurchaseName => {
     if (!isSlotPurchaseName(slotPurchaseName)) throw new Error(`invalid slot name ${slotPurchaseName}`);
     return slotPurchaseName;
 };
diff --git a/src/helpers/stringHelpers.ts b/src/helpers/stringHelpers.ts
index ea6e47ef..89a3ae9d 100644
--- a/src/helpers/stringHelpers.ts
+++ b/src/helpers/stringHelpers.ts
@@ -17,7 +17,7 @@ export const getSubstringFromKeywordToKeyword = (str: string, keywordBegin: stri
     return str.substring(beginIndex, endIndex + 1);
 };
 
-export const getIndexAfter = (str: string, searchWord: string) => {
+export const getIndexAfter = (str: string, searchWord: string): number => {
     const index = str.indexOf(searchWord);
     if (index === -1) {
         return -1;
diff --git a/src/middleware/middleware.ts b/src/middleware/middleware.ts
index 68e60191..96fe391c 100644
--- a/src/middleware/middleware.ts
+++ b/src/middleware/middleware.ts
@@ -1,7 +1,7 @@
 import { logger } from "@/src/utils/logger";
 import { /*NextFunction,*/ Request, Response } from "express";
 
-const unknownEndpointHandler = (request: Request, response: Response) => {
+const unknownEndpointHandler = (request: Request, response: Response): void => {
     logger.error(`unknown endpoint ${request.method} ${request.path}`);
     if (request.body) {
         logger.debug(`data provided to ${request.path}: ${String(request.body)}`);
diff --git a/src/models/inventoryModels/inventoryModel.ts b/src/models/inventoryModels/inventoryModel.ts
index c49e8eb6..304a6962 100644
--- a/src/models/inventoryModels/inventoryModel.ts
+++ b/src/models/inventoryModels/inventoryModel.ts
@@ -316,7 +316,7 @@ const MailboxSchema = new Schema<IMailbox>(
     {
         LastInboxId: {
             type: Schema.Types.ObjectId,
-            set: (v: IMailbox["LastInboxId"]) => v.$oid.toString()
+            set: (v: IMailbox["LastInboxId"]): string => v.$oid.toString()
         }
     },
     { id: false, _id: false }
diff --git a/src/services/configService.ts b/src/services/configService.ts
index ab16cb7e..bcb2ff4d 100644
--- a/src/services/configService.ts
+++ b/src/services/configService.ts
@@ -47,7 +47,7 @@ interface ILoggerConfig {
     level: string; // "fatal" | "error" | "warn" | "info" | "http" | "debug" | "trace";
 }
 
-export const updateConfig = async (data: string) => {
+export const updateConfig = async (data: string): Promise<void> => {
     amnesia = true;
     await fsPromises.writeFile(configPath, data);
     Object.assign(config, JSON.parse(data));
diff --git a/src/services/inventoryService.ts b/src/services/inventoryService.ts
index 4f5bbb17..d67d7e73 100644
--- a/src/services/inventoryService.ts
+++ b/src/services/inventoryService.ts
@@ -42,7 +42,7 @@ import {
 export const createInventory = async (
     accountOwnerId: Types.ObjectId,
     defaultItemReferences: { loadOutPresetId: Types.ObjectId; ship: Types.ObjectId }
-) => {
+): Promise<void> => {
     try {
         const inventory = new Inventory({
             ...new_inventory,
@@ -405,7 +405,12 @@ export const addSpaceSuit = async (spacesuitName: string, accountId: string) =>
     return changedInventory.SpaceSuits[suitIndex - 1].toJSON();
 };
 
-export const updateSlots = async (accountId: string, slotName: SlotNames, slotAmount: number, extraAmount: number) => {
+export const updateSlots = async (
+    accountId: string,
+    slotName: SlotNames,
+    slotAmount: number,
+    extraAmount: number
+): Promise<void> => {
     const inventory = await getInventory(accountId);
 
     inventory[slotName].Slots += slotAmount;
@@ -478,7 +483,7 @@ export const updateGeneric = async (data: IGenericUpdate, accountId: string): Pr
     await inventory.save();
 };
 
-export const updateTheme = async (data: IThemeUpdateRequest, accountId: string) => {
+export const updateTheme = async (data: IThemeUpdateRequest, accountId: string): Promise<void> => {
     const inventory = await getInventory(accountId);
     if (data.Style) inventory.ThemeStyle = data.Style;
     if (data.Background) inventory.ThemeBackground = data.Background;
@@ -546,7 +551,7 @@ const addGearExpByCategory = (
     inventory: IInventoryDatabaseDocument,
     gearArray: IEquipmentClient[] | undefined,
     categoryName: TEquipmentKey
-) => {
+): void => {
     const category = inventory[categoryName];
 
     gearArray?.forEach(({ ItemId, XP }) => {
@@ -575,7 +580,7 @@ const addGearExpByCategory = (
     });
 };
 
-export const addMiscItems = (inventory: IInventoryDatabaseDocument, itemsArray: IMiscItem[] | undefined) => {
+export const addMiscItems = (inventory: IInventoryDatabaseDocument, itemsArray: IMiscItem[] | undefined): void => {
     const { MiscItems } = inventory;
 
     itemsArray?.forEach(({ ItemCount, ItemType }) => {
@@ -590,7 +595,10 @@ export const addMiscItems = (inventory: IInventoryDatabaseDocument, itemsArray:
     });
 };
 
-export const addShipDecorations = (inventory: IInventoryDatabaseDocument, itemsArray: IConsumable[] | undefined) => {
+export const addShipDecorations = (
+    inventory: IInventoryDatabaseDocument,
+    itemsArray: IConsumable[] | undefined
+): void => {
     const { ShipDecorations } = inventory;
 
     itemsArray?.forEach(({ ItemCount, ItemType }) => {
@@ -605,7 +613,7 @@ export const addShipDecorations = (inventory: IInventoryDatabaseDocument, itemsA
     });
 };
 
-export const addConsumables = (inventory: IInventoryDatabaseDocument, itemsArray: IConsumable[] | undefined) => {
+export const addConsumables = (inventory: IInventoryDatabaseDocument, itemsArray: IConsumable[] | undefined): void => {
     const { Consumables } = inventory;
 
     itemsArray?.forEach(({ ItemCount, ItemType }) => {
@@ -620,7 +628,7 @@ export const addConsumables = (inventory: IInventoryDatabaseDocument, itemsArray
     });
 };
 
-export const addRecipes = (inventory: IInventoryDatabaseDocument, itemsArray: ITypeCount[] | undefined) => {
+export const addRecipes = (inventory: IInventoryDatabaseDocument, itemsArray: ITypeCount[] | undefined): void => {
     const { Recipes } = inventory;
 
     itemsArray?.forEach(({ ItemCount, ItemType }) => {
@@ -635,7 +643,7 @@ export const addRecipes = (inventory: IInventoryDatabaseDocument, itemsArray: IT
     });
 };
 
-export const addMods = (inventory: IInventoryDatabaseDocument, itemsArray: IRawUpgrade[] | undefined) => {
+export const addMods = (inventory: IInventoryDatabaseDocument, itemsArray: IRawUpgrade[] | undefined): void => {
     const { RawUpgrades } = inventory;
     itemsArray?.forEach(({ ItemType, ItemCount }) => {
         const itemIndex = RawUpgrades.findIndex(i => i.ItemType === ItemType);
@@ -652,7 +660,7 @@ export const addMods = (inventory: IInventoryDatabaseDocument, itemsArray: IRawU
 export const addFusionTreasures = (
     inventory: IInventoryDatabaseDocument,
     itemsArray: IFusionTreasure[] | undefined
-) => {
+): void => {
     const { FusionTreasures } = inventory;
     itemsArray?.forEach(({ ItemType, ItemCount, Sockets }) => {
         const itemIndex = FusionTreasures.findIndex(i => i.ItemType == ItemType && (i.Sockets || 0) == (Sockets || 0));
@@ -666,7 +674,10 @@ export const addFusionTreasures = (
     });
 };
 
-export const updateChallengeProgress = async (challenges: IUpdateChallengeProgressRequest, accountId: string) => {
+export const updateChallengeProgress = async (
+    challenges: IUpdateChallengeProgressRequest,
+    accountId: string
+): Promise<void> => {
     const inventory = await getInventory(accountId);
 
     addChallenges(inventory, challenges.ChallengeProgress);
@@ -678,7 +689,7 @@ export const updateChallengeProgress = async (challenges: IUpdateChallengeProgre
 export const addSeasonalChallengeHistory = (
     inventory: IInventoryDatabaseDocument,
     itemsArray: ISeasonChallenge[] | undefined
-) => {
+): void => {
     const category = inventory.SeasonChallengeHistory;
 
     itemsArray?.forEach(({ challenge, id }) => {
@@ -692,7 +703,10 @@ export const addSeasonalChallengeHistory = (
     });
 };
 
-export const addChallenges = (inventory: IInventoryDatabaseDocument, itemsArray: IChallengeProgress[] | undefined) => {
+export const addChallenges = (
+    inventory: IInventoryDatabaseDocument,
+    itemsArray: IChallengeProgress[] | undefined
+): void => {
     const category = inventory.ChallengeProgress;
 
     itemsArray?.forEach(({ Name, Progress }) => {
@@ -707,7 +721,7 @@ export const addChallenges = (inventory: IInventoryDatabaseDocument, itemsArray:
     });
 };
 
-const addMissionComplete = (inventory: IInventoryDatabaseDocument, { Tag, Completes }: IMission) => {
+const addMissionComplete = (inventory: IInventoryDatabaseDocument, { Tag, Completes }: IMission): void => {
     const { Missions } = inventory;
     const itemIndex = Missions.findIndex(item => item.Tag === Tag);
 
@@ -719,7 +733,10 @@ const addMissionComplete = (inventory: IInventoryDatabaseDocument, { Tag, Comple
     }
 };
 
-export const missionInventoryUpdate = async (data: IMissionInventoryUpdateRequest, accountId: string) => {
+export const missionInventoryUpdate = async (
+    data: IMissionInventoryUpdateRequest,
+    accountId: string
+): Promise<IInventoryChanges> => {
     const {
         RawUpgrades,
         MiscItems,
diff --git a/src/services/loadoutService.ts b/src/services/loadoutService.ts
index 37f91612..8ca415f8 100644
--- a/src/services/loadoutService.ts
+++ b/src/services/loadoutService.ts
@@ -1,7 +1,8 @@
 import { Loadout } from "@/src/models/inventoryModels/loadoutModel";
 import { logger } from "@/src/utils/logger";
+import { ILoadoutDatabase } from "../types/saveLoadoutTypes";
 
-export const getLoadout = async (accountId: string) => {
+export const getLoadout = async (accountId: string): Promise<ILoadoutDatabase> => {
     const loadout = await Loadout.findOne({ loadoutOwnerId: accountId });
 
     if (!loadout) {
@@ -9,5 +10,5 @@ export const getLoadout = async (accountId: string) => {
         throw new Error("loadout not found");
     }
 
-    return loadout;
+    return loadout.toJSON();
 };
diff --git a/src/services/loginService.ts b/src/services/loginService.ts
index 3ddb7982..d50a729a 100644
--- a/src/services/loginService.ts
+++ b/src/services/loginService.ts
@@ -29,13 +29,13 @@ export const createAccount = async (accountData: IDatabaseAccount) => {
     }
 };
 
-export const createLoadout = async (accountId: Types.ObjectId) => {
+export const createLoadout = async (accountId: Types.ObjectId): Promise<Types.ObjectId> => {
     const loadout = new Loadout({ loadoutOwnerId: accountId });
     const savedLoadout = await loadout.save();
     return savedLoadout._id;
 };
 
-export const createPersonalRooms = async (accountId: Types.ObjectId, shipId: Types.ObjectId) => {
+export const createPersonalRooms = async (accountId: Types.ObjectId, shipId: Types.ObjectId): Promise<void> => {
     const personalRooms = new PersonalRooms({
         ...new_personal_rooms,
         personalRoomsOwnerId: accountId,
diff --git a/src/services/missionInventoryUpdateService.ts b/src/services/missionInventoryUpdateService.ts
index ad633117..f4b8d4f2 100644
--- a/src/services/missionInventoryUpdateService.ts
+++ b/src/services/missionInventoryUpdateService.ts
@@ -184,7 +184,7 @@ const addRewardResponse = (
     ItemType: string,
     ItemCount: number,
     InventoryCategory: IInventoryFieldType
-) => {
+): void => {
     if (!ItemType) return;
 
     if (!InventoryChanges[InventoryCategory]) {
diff --git a/src/services/mongoService.ts b/src/services/mongoService.ts
index a90b6f8e..8b8f5838 100644
--- a/src/services/mongoService.ts
+++ b/src/services/mongoService.ts
@@ -8,7 +8,7 @@ if (url === undefined) {
     throw new Error("MONGODB_URL not found. Make sure you have a .env file in the root of the project!");
 }
 
-const connectDatabase = async () => {
+const connectDatabase = async (): Promise<void> => {
     try {
         await mongoose.connect(`${url}`);
         logger.info("Connected to MongoDB");
diff --git a/src/services/purchaseService.ts b/src/services/purchaseService.ts
index 29bdc218..28458775 100644
--- a/src/services/purchaseService.ts
+++ b/src/services/purchaseService.ts
@@ -11,13 +11,13 @@ import { IPurchaseRequest, SlotPurchase, IInventoryChanges } from "@/src/types/p
 import { logger } from "@/src/utils/logger";
 import { ExportBundles, ExportGear, TRarity } from "warframe-public-export-plus";
 
-export const getStoreItemCategory = (storeItem: string) => {
+export const getStoreItemCategory = (storeItem: string): string => {
     const storeItemString = getSubstringFromKeyword(storeItem, "StoreItems/");
     const storeItemElements = storeItemString.split("/");
     return storeItemElements[1];
 };
 
-export const getStoreItemTypesCategory = (typesItem: string) => {
+export const getStoreItemTypesCategory = (typesItem: string): string => {
     const typesString = getSubstringFromKeyword(typesItem, "Types");
     const typeElements = typesString.split("/");
     if (typesItem.includes("StoreItems")) {
@@ -26,7 +26,10 @@ export const getStoreItemTypesCategory = (typesItem: string) => {
     return typeElements[1];
 };
 
-export const handlePurchase = async (purchaseRequest: IPurchaseRequest, accountId: string) => {
+export const handlePurchase = async (
+    purchaseRequest: IPurchaseRequest,
+    accountId: string
+): Promise<{ InventoryChanges: IInventoryChanges }> => {
     logger.debug("purchase request", purchaseRequest);
 
     const purchaseResponse = await handleStoreItemAcquisition(
diff --git a/src/services/recipeService.ts b/src/services/recipeService.ts
index 8594def4..85d19d6e 100644
--- a/src/services/recipeService.ts
+++ b/src/services/recipeService.ts
@@ -4,7 +4,7 @@ import { getRecipe } from "@/src/services/itemDataService";
 import { logger } from "@/src/utils/logger";
 import { Types } from "mongoose";
 
-export const startRecipe = async (recipeName: string, accountId: string) => {
+export const startRecipe = async (recipeName: string, accountId: string): Promise<{ RecipeId: { $oid?: string } }> => {
     const recipe = getRecipe(recipeName);
 
     if (!recipe) {
diff --git a/src/services/shipCustomizationsService.ts b/src/services/shipCustomizationsService.ts
index 170a69f0..fb71eafa 100644
--- a/src/services/shipCustomizationsService.ts
+++ b/src/services/shipCustomizationsService.ts
@@ -10,7 +10,7 @@ import {
 import { logger } from "@/src/utils/logger";
 import { Types } from "mongoose";
 
-export const setShipCustomizations = async (shipCustomization: ISetShipCustomizationsRequest) => {
+export const setShipCustomizations = async (shipCustomization: ISetShipCustomizationsRequest): Promise<void> => {
     const ship = await getShip(new Types.ObjectId(shipCustomization.ShipId));
 
     let shipChanges: Partial<IShipDatabase>;
diff --git a/src/services/shipService.ts b/src/services/shipService.ts
index ae11c9d2..f43772f1 100644
--- a/src/services/shipService.ts
+++ b/src/services/shipService.ts
@@ -3,7 +3,7 @@ import { ILoadoutDatabase } from "@/src/types/saveLoadoutTypes";
 import { logger } from "@/src/utils/logger";
 import { Types } from "mongoose";
 
-export const createShip = async (accountOwnerId: Types.ObjectId) => {
+export const createShip = async (accountOwnerId: Types.ObjectId): Promise<Types.ObjectId> => {
     try {
         const ship = new Ship({
             ItemType: "/Lotus/Types/Items/Ships/DefaultShip",
diff --git a/src/utils/logger.ts b/src/utils/logger.ts
index 03aa2562..2ca65ec6 100644
--- a/src/utils/logger.ts
+++ b/src/utils/logger.ts
@@ -103,7 +103,7 @@ export const logger = createLogger({
 
 addColors(logLevels.colors);
 
-export function registerLogFileCreationListener() {
+export function registerLogFileCreationListener(): void {
     errorLog.on("new", filename => logger.info(`Using error log file: ${filename}`));
     combinedLog.on("new", filename => logger.info(`Using combined log file: ${filename}`));
     errorLog.on("rotate", filename => logger.info(`Rotated error log file: ${filename}`));