diff --git a/apps/bff/src/integrations/freebit/interfaces/freebit.types.ts b/apps/bff/src/integrations/freebit/interfaces/freebit.types.ts
index b8ff72c4..62fc96bf 100644
--- a/apps/bff/src/integrations/freebit/interfaces/freebit.types.ts
+++ b/apps/bff/src/integrations/freebit/interfaces/freebit.types.ts
@@ -92,6 +92,7 @@ export interface FreebitTopUpRequest {
   quota: number; // KB units (e.g., 102400 for 100MB)
   quotaCode?: string; // Campaign code
   expire?: string; // YYYYMMDD format
+  runTime?: string; // Scheduled execution time (YYYYMMDDHHmm)
 }
 
 export interface FreebitTopUpResponse {
@@ -235,7 +236,13 @@ export interface FreebitCancelAccountResponse {
 
 export interface FreebitEsimReissueRequest {
   authKey: string;
-  account: string;
+  requestDatas: Array<{
+    kind: "MVNO";
+    account: string;
+    newEid?: string;
+    oldEid?: string;
+    planCode?: string;
+  }>;
 }
 
 export interface FreebitEsimReissueResponse {
diff --git a/apps/bff/src/integrations/freebit/services/freebit-operations.service.ts b/apps/bff/src/integrations/freebit/services/freebit-operations.service.ts
index 7be7f482..37a6393b 100644
--- a/apps/bff/src/integrations/freebit/services/freebit-operations.service.ts
+++ b/apps/bff/src/integrations/freebit/services/freebit-operations.service.ts
@@ -144,7 +144,7 @@ export class FreebitOperationsService {
   ): Promise<void> {
     try {
       const quotaKb = Math.round(quotaMb * 1024);
-      const request: Omit<FreebitTopUpRequest, "authKey"> = {
+      const baseRequest: Omit<FreebitTopUpRequest, "authKey"> = {
         account,
         quota: quotaKb,
         quotaCode: options.campaignCode,
@@ -153,9 +153,7 @@ export class FreebitOperationsService {
 
       const scheduled = !!options.scheduledAt;
       const endpoint = scheduled ? "/mvno/eachQuota/" : "/master/addSpec/";
-      if (scheduled) {
-        (request as any).runTime = options.scheduledAt;
-      }
+      const request = scheduled ? { ...baseRequest, runTime: options.scheduledAt } : baseRequest;
 
       await this.client.makeAuthenticatedRequest<FreebitTopUpResponse, typeof request>(
         endpoint,
@@ -348,7 +346,7 @@ export class FreebitOperationsService {
     try {
       const request: Omit<FreebitEsimReissueRequest, "authKey"> = {
         requestDatas: [{ kind: "MVNO", account }],
-      } as any;
+      };
 
       await this.client.makeAuthenticatedRequest<FreebitEsimReissueResponse, typeof request>(
         "/mvno/reissueEsim/",
diff --git a/apps/bff/src/integrations/freebit/services/freebit-orchestrator.service.ts b/apps/bff/src/integrations/freebit/services/freebit-orchestrator.service.ts
index 0b4fcdf9..1b1a10e6 100644
--- a/apps/bff/src/integrations/freebit/services/freebit-orchestrator.service.ts
+++ b/apps/bff/src/integrations/freebit/services/freebit-orchestrator.service.ts
@@ -1,12 +1,7 @@
 import { Injectable } from "@nestjs/common";
 import { FreebitOperationsService } from "./freebit-operations.service";
 import { FreebitMapperService } from "./freebit-mapper.service";
-import type {
-  SimDetails,
-  SimUsage,
-  SimTopUpHistory,
-  FreebitEsimAddAccountRequest,
-} from "../interfaces/freebit.types";
+import type { SimDetails, SimUsage, SimTopUpHistory } from "../interfaces/freebit.types";
 
 @Injectable()
 export class FreebitOrchestratorService {
diff --git a/apps/bff/src/integrations/salesforce/events/pubsub.subscriber.ts b/apps/bff/src/integrations/salesforce/events/pubsub.subscriber.ts
index e58fb0d3..9f962de6 100644
--- a/apps/bff/src/integrations/salesforce/events/pubsub.subscriber.ts
+++ b/apps/bff/src/integrations/salesforce/events/pubsub.subscriber.ts
@@ -15,12 +15,13 @@ import type {
   SalesforcePubSubError,
   SalesforcePubSubSubscription,
   SalesforcePubSubCallbackType,
+  SalesforcePubSubUnknownData,
 } from "../types/pubsub-events.types";
 
 type SubscribeCallback = (
   subscription: SalesforcePubSubSubscription,
   callbackType: SalesforcePubSubCallbackType,
-  data: SalesforcePubSubEvent | SalesforcePubSubError | unknown
+  data: SalesforcePubSubEvent | SalesforcePubSubError | SalesforcePubSubUnknownData
 ) => void | Promise<void>;
 
 interface PubSubClient {
diff --git a/apps/bff/src/integrations/salesforce/types/pubsub-events.types.ts b/apps/bff/src/integrations/salesforce/types/pubsub-events.types.ts
index d4db9c62..948aaa35 100644
--- a/apps/bff/src/integrations/salesforce/types/pubsub-events.types.ts
+++ b/apps/bff/src/integrations/salesforce/types/pubsub-events.types.ts
@@ -33,8 +33,10 @@ export interface SalesforcePubSubError {
 
 export type SalesforcePubSubCallbackType = "data" | "event" | "grpcstatus" | "end" | "error";
 
+export type SalesforcePubSubUnknownData = Record<string, unknown> | null | undefined;
+
 export interface SalesforcePubSubCallback {
   subscription: SalesforcePubSubSubscription;
   callbackType: SalesforcePubSubCallbackType;
-  data: SalesforcePubSubEvent | SalesforcePubSubError | unknown;
+  data: SalesforcePubSubEvent | SalesforcePubSubError | SalesforcePubSubUnknownData;
 }
diff --git a/apps/bff/src/integrations/whmcs/connection/services/whmcs-connection-orchestrator.service.ts b/apps/bff/src/integrations/whmcs/connection/services/whmcs-connection-orchestrator.service.ts
index 6a504ad7..ea622763 100644
--- a/apps/bff/src/integrations/whmcs/connection/services/whmcs-connection-orchestrator.service.ts
+++ b/apps/bff/src/integrations/whmcs/connection/services/whmcs-connection-orchestrator.service.ts
@@ -6,7 +6,6 @@ import { WhmcsHttpClientService } from "./whmcs-http-client.service";
 import { WhmcsErrorHandlerService } from "./whmcs-error-handler.service";
 import { WhmcsApiMethodsService } from "./whmcs-api-methods.service";
 import type {
-  WhmcsApiResponse,
   WhmcsErrorResponse,
   WhmcsAddClientParams,
   WhmcsValidateLoginParams,
diff --git a/apps/bff/src/integrations/whmcs/connection/services/whmcs-error-handler.service.ts b/apps/bff/src/integrations/whmcs/connection/services/whmcs-error-handler.service.ts
index ead43d6e..7b9fdab9 100644
--- a/apps/bff/src/integrations/whmcs/connection/services/whmcs-error-handler.service.ts
+++ b/apps/bff/src/integrations/whmcs/connection/services/whmcs-error-handler.service.ts
@@ -44,7 +44,7 @@ export class WhmcsErrorHandlerService {
   /**
    * Handle general request errors (network, timeout, etc.)
    */
-  handleRequestError(error: unknown, action: string, params: Record<string, unknown>): never {
+  handleRequestError(error: unknown, action: string, _params: Record<string, unknown>): never {
     const message = getErrorMessage(error);
 
     if (this.isTimeoutError(error)) {
diff --git a/apps/bff/src/integrations/whmcs/connection/services/whmcs-http-client.service.ts b/apps/bff/src/integrations/whmcs/connection/services/whmcs-http-client.service.ts
index 17f0a8e4..7368b9f9 100644
--- a/apps/bff/src/integrations/whmcs/connection/services/whmcs-http-client.service.ts
+++ b/apps/bff/src/integrations/whmcs/connection/services/whmcs-http-client.service.ts
@@ -189,14 +189,53 @@ export class WhmcsHttpClientService {
 
     // Add parameters
     for (const [key, value] of Object.entries(params)) {
-      if (value !== undefined && value !== null) {
-        formData.append(key, String(value));
+      if (value === undefined || value === null) {
+        continue;
       }
+
+      const serialized = this.serializeParamValue(value);
+      formData.append(key, serialized);
     }
 
     return formData.toString();
   }
 
+  private serializeParamValue(value: unknown): string {
+    if (typeof value === "string") {
+      return value;
+    }
+
+    if (typeof value === "number" || typeof value === "boolean" || typeof value === "bigint") {
+      return String(value);
+    }
+
+    if (value instanceof Date) {
+      return value.toISOString();
+    }
+
+    if (Array.isArray(value)) {
+      return value.map(entry => this.serializeParamValue(entry)).join(",");
+    }
+
+    if (typeof value === "object" && value !== null) {
+      try {
+        return JSON.stringify(value);
+      } catch {
+        return Object.prototype.toString.call(value);
+      }
+    }
+
+    if (typeof value === "symbol") {
+      return value.description ? `Symbol(${value.description})` : "Symbol()";
+    }
+
+    if (typeof value === "function") {
+      return value.name ? `[Function ${value.name}]` : "[Function anonymous]";
+    }
+
+    return Object.prototype.toString.call(value);
+  }
+
   /**
    * Parse WHMCS API response
    */
diff --git a/apps/bff/src/integrations/whmcs/services/whmcs-invoice.service.ts b/apps/bff/src/integrations/whmcs/services/whmcs-invoice.service.ts
index 14b66704..24f9904c 100644
--- a/apps/bff/src/integrations/whmcs/services/whmcs-invoice.service.ts
+++ b/apps/bff/src/integrations/whmcs/services/whmcs-invoice.service.ts
@@ -4,7 +4,7 @@ import { Injectable, NotFoundException, Inject } from "@nestjs/common";
 import { Invoice, InvoiceList } from "@customer-portal/domain";
 import {
   invoiceListSchema,
-  invoiceSchema as invoiceEntitySchema,
+  invoiceSchema,
 } from "@customer-portal/domain/validation/shared/entities";
 import { WhmcsConnectionOrchestratorService } from "../connection/services/whmcs-connection-orchestrator.service";
 import { InvoiceTransformerService } from "../transformers/services/invoice-transformer.service";
@@ -15,9 +15,6 @@ import {
   WhmcsCreateInvoiceParams,
   WhmcsUpdateInvoiceParams,
   WhmcsCapturePaymentParams,
-  WhmcsCreateInvoiceResponse,
-  WhmcsUpdateInvoiceResponse,
-  WhmcsCapturePaymentResponse,
 } from "../types/whmcs-api.types";
 
 export interface InvoiceFilters {
@@ -88,7 +85,7 @@ export class WhmcsInvoiceService {
       this.logger.log(
         `Fetched ${result.invoices.length} invoices for client ${clientId}, page ${page}`
       );
-      return result;
+      return result as InvoiceList;
     } catch (error) {
       this.logger.error(`Failed to fetch invoices for client ${clientId}`, {
         error: getErrorMessage(error),
@@ -117,7 +114,7 @@ export class WhmcsInvoiceService {
           try {
             // Get detailed invoice with items
             const detailedInvoice = await this.getInvoiceById(clientId, userId, invoice.id);
-            const parseResult = invoiceEntitySchema.safeParse(detailedInvoice);
+            const parseResult = invoiceSchema.safeParse(detailedInvoice);
             if (!parseResult.success) {
               this.logger.error("Failed to parse detailed invoice", {
                 error: parseResult.error.issues,
@@ -139,7 +136,7 @@ export class WhmcsInvoiceService {
       );
 
       const result: InvoiceList = {
-        invoices: invoicesWithItems,
+        invoices: invoicesWithItems as Invoice[],
         pagination: invoiceList.pagination,
       };
 
@@ -184,7 +181,7 @@ export class WhmcsInvoiceService {
       // Transform invoice
       const invoice = this.invoiceTransformer.transformInvoice(response);
 
-      const parseResult = invoiceEntitySchema.safeParse(invoice);
+      const parseResult = invoiceSchema.safeParse(invoice);
       if (!parseResult.success) {
         throw new Error(`Invalid invoice data after transformation`);
       }
@@ -232,8 +229,8 @@ export class WhmcsInvoiceService {
     for (const whmcsInvoice of response.invoices.invoice) {
       try {
         const transformed = this.invoiceTransformer.transformInvoice(whmcsInvoice);
-        const parsed = invoiceEntitySchema.parse(transformed);
-        invoices.push(parsed);
+        const parsed = invoiceSchema.parse(transformed);
+        invoices.push(parsed as Invoice);
       } catch (error) {
         this.logger.error(`Failed to transform invoice ${whmcsInvoice.id}`, {
           error: getErrorMessage(error),
diff --git a/apps/bff/src/integrations/whmcs/transformers/services/invoice-transformer.service.ts b/apps/bff/src/integrations/whmcs/transformers/services/invoice-transformer.service.ts
index cbbc03e3..0c8a2595 100644
--- a/apps/bff/src/integrations/whmcs/transformers/services/invoice-transformer.service.ts
+++ b/apps/bff/src/integrations/whmcs/transformers/services/invoice-transformer.service.ts
@@ -1,11 +1,7 @@
 import { Injectable, Inject } from "@nestjs/common";
 import { Logger } from "nestjs-pino";
 import { Invoice, InvoiceItem as BaseInvoiceItem } from "@customer-portal/domain";
-import type {
-  WhmcsInvoice,
-  WhmcsInvoiceItems,
-  WhmcsCustomField,
-} from "../../types/whmcs-api.types";
+import type { WhmcsInvoice, WhmcsInvoiceItems } from "../../types/whmcs-api.types";
 import { DataUtils } from "../utils/data-utils";
 import { StatusNormalizer } from "../utils/status-normalizer";
 import { TransformationValidator } from "../validators/transformation-validator";
diff --git a/apps/bff/src/integrations/whmcs/transformers/services/subscription-transformer.service.ts b/apps/bff/src/integrations/whmcs/transformers/services/subscription-transformer.service.ts
index 43248b4b..01b4bbba 100644
--- a/apps/bff/src/integrations/whmcs/transformers/services/subscription-transformer.service.ts
+++ b/apps/bff/src/integrations/whmcs/transformers/services/subscription-transformer.service.ts
@@ -131,7 +131,7 @@ export class SubscriptionTransformerService {
   private normalizeFieldName(name: string): string {
     return name
       .toLowerCase()
-      .replace(/[^a-z0-9]+(.)/g, (_, char) => char.toUpperCase())
+      .replace(/[^a-z0-9]+(.)/g, (_match: string, char: string) => char.toUpperCase())
       .replace(/^[^a-z]+/, "");
   }
 
diff --git a/apps/bff/src/integrations/whmcs/transformers/services/whmcs-transformer-orchestrator.service.ts b/apps/bff/src/integrations/whmcs/transformers/services/whmcs-transformer-orchestrator.service.ts
index 48f4d849..3721fbdf 100644
--- a/apps/bff/src/integrations/whmcs/transformers/services/whmcs-transformer-orchestrator.service.ts
+++ b/apps/bff/src/integrations/whmcs/transformers/services/whmcs-transformer-orchestrator.service.ts
@@ -30,7 +30,7 @@ export class WhmcsTransformerOrchestratorService {
   /**
    * Transform WHMCS invoice to our standard Invoice format
    */
-  async transformInvoice(whmcsInvoice: WhmcsInvoice): Promise<Invoice> {
+  transformInvoice(whmcsInvoice: WhmcsInvoice): Invoice {
     try {
       return this.invoiceTransformer.transformInvoice(whmcsInvoice);
     } catch (error) {
@@ -60,7 +60,7 @@ export class WhmcsTransformerOrchestratorService {
   /**
    * Transform WHMCS product/service to our standard Subscription format
    */
-  async transformSubscription(whmcsProduct: WhmcsProduct): Promise<Subscription> {
+  transformSubscription(whmcsProduct: WhmcsProduct): Subscription {
     try {
       return this.subscriptionTransformer.transformSubscription(whmcsProduct);
     } catch (error) {
@@ -90,7 +90,7 @@ export class WhmcsTransformerOrchestratorService {
   /**
    * Transform WHMCS payment gateway to shared PaymentGateway interface
    */
-  async transformPaymentGateway(whmcsGateway: WhmcsPaymentGateway): Promise<PaymentGateway> {
+  transformPaymentGateway(whmcsGateway: WhmcsPaymentGateway): PaymentGateway {
     try {
       return this.paymentTransformer.transformPaymentGateway(whmcsGateway);
     } catch (error) {
@@ -120,7 +120,7 @@ export class WhmcsTransformerOrchestratorService {
   /**
    * Transform WHMCS payment method to shared PaymentMethod interface
    */
-  async transformPaymentMethod(whmcsPayMethod: WhmcsPaymentMethod): Promise<PaymentMethod> {
+  transformPaymentMethod(whmcsPayMethod: WhmcsPaymentMethod): PaymentMethod {
     try {
       return this.paymentTransformer.transformPaymentMethod(whmcsPayMethod);
     } catch (error) {
@@ -150,16 +150,16 @@ export class WhmcsTransformerOrchestratorService {
   /**
    * Transform multiple invoices in batch with error handling
    */
-  async transformInvoices(whmcsInvoices: WhmcsInvoice[]): Promise<{
+  transformInvoices(whmcsInvoices: WhmcsInvoice[]): {
     successful: Invoice[];
     failed: Array<{ invoice: WhmcsInvoice; error: string }>;
-  }> {
+  } {
     const successful: Invoice[] = [];
     const failed: Array<{ invoice: WhmcsInvoice; error: string }> = [];
 
     for (const whmcsInvoice of whmcsInvoices) {
       try {
-        const transformed = await this.transformInvoice(whmcsInvoice);
+        const transformed = this.transformInvoice(whmcsInvoice);
         successful.push(transformed);
       } catch (error) {
         failed.push({
@@ -181,16 +181,16 @@ export class WhmcsTransformerOrchestratorService {
   /**
    * Transform multiple subscriptions in batch with error handling
    */
-  async transformSubscriptions(whmcsProducts: WhmcsProduct[]): Promise<{
+  transformSubscriptions(whmcsProducts: WhmcsProduct[]): {
     successful: Subscription[];
     failed: Array<{ product: WhmcsProduct; error: string }>;
-  }> {
+  } {
     const successful: Subscription[] = [];
     const failed: Array<{ product: WhmcsProduct; error: string }> = [];
 
     for (const whmcsProduct of whmcsProducts) {
       try {
-        const transformed = await this.transformSubscription(whmcsProduct);
+        const transformed = this.transformSubscription(whmcsProduct);
         successful.push(transformed);
       } catch (error) {
         failed.push({
@@ -212,16 +212,16 @@ export class WhmcsTransformerOrchestratorService {
   /**
    * Transform multiple payment methods in batch with error handling
    */
-  async transformPaymentMethods(whmcsPayMethods: WhmcsPaymentMethod[]): Promise<{
+  transformPaymentMethods(whmcsPayMethods: WhmcsPaymentMethod[]): {
     successful: PaymentMethod[];
     failed: Array<{ payMethod: WhmcsPaymentMethod; error: string }>;
-  }> {
+  } {
     const successful: PaymentMethod[] = [];
     const failed: Array<{ payMethod: WhmcsPaymentMethod; error: string }> = [];
 
     for (const whmcsPayMethod of whmcsPayMethods) {
       try {
-        const transformed = await this.transformPaymentMethod(whmcsPayMethod);
+        const transformed = this.transformPaymentMethod(whmcsPayMethod);
         successful.push(transformed);
       } catch (error) {
         failed.push({
@@ -243,16 +243,16 @@ export class WhmcsTransformerOrchestratorService {
   /**
    * Transform multiple payment gateways in batch with error handling
    */
-  async transformPaymentGateways(whmcsGateways: WhmcsPaymentGateway[]): Promise<{
+  transformPaymentGateways(whmcsGateways: WhmcsPaymentGateway[]): {
     successful: PaymentGateway[];
     failed: Array<{ gateway: WhmcsPaymentGateway; error: string }>;
-  }> {
+  } {
     const successful: PaymentGateway[] = [];
     const failed: Array<{ gateway: WhmcsPaymentGateway; error: string }> = [];
 
     for (const whmcsGateway of whmcsGateways) {
       try {
-        const transformed = await this.transformPaymentGateway(whmcsGateway);
+        const transformed = this.transformPaymentGateway(whmcsGateway);
         successful.push(transformed);
       } catch (error) {
         failed.push({
diff --git a/apps/bff/src/integrations/whmcs/transformers/utils/data-utils.ts b/apps/bff/src/integrations/whmcs/transformers/utils/data-utils.ts
index 43a23aad..d119b353 100644
--- a/apps/bff/src/integrations/whmcs/transformers/utils/data-utils.ts
+++ b/apps/bff/src/integrations/whmcs/transformers/utils/data-utils.ts
@@ -126,18 +126,59 @@ export class DataUtils {
     if (!customFields) return undefined;
 
     // Try exact match first
-    if (customFields[fieldName]) {
-      return String(customFields[fieldName]);
+    const directValue = DataUtils.toStringValue(customFields[fieldName]);
+    if (directValue !== undefined) {
+      return directValue;
     }
 
     // Try case-insensitive match
     const lowerFieldName = fieldName.toLowerCase();
     for (const [key, value] of Object.entries(customFields)) {
       if (key.toLowerCase() === lowerFieldName) {
-        return String(value);
+        return DataUtils.toStringValue(value);
       }
     }
 
     return undefined;
   }
+
+  private static toStringValue(value: unknown): string | undefined {
+    if (value === undefined || value === null) {
+      return undefined;
+    }
+
+    if (typeof value === "string") {
+      return value;
+    }
+
+    if (typeof value === "number" || typeof value === "boolean" || typeof value === "bigint") {
+      return String(value);
+    }
+
+    if (value instanceof Date) {
+      return value.toISOString();
+    }
+
+    if (Array.isArray(value)) {
+      return value.map(entry => DataUtils.toStringValue(entry) ?? "").join(",");
+    }
+
+    if (typeof value === "object") {
+      try {
+        return JSON.stringify(value);
+      } catch {
+        return Object.prototype.toString.call(value);
+      }
+    }
+
+    if (typeof value === "symbol") {
+      return value.description ? `Symbol(${value.description})` : "Symbol()";
+    }
+
+    if (typeof value === "function") {
+      return value.name ? `[Function ${value.name}]` : "[Function anonymous]";
+    }
+
+    return Object.prototype.toString.call(value);
+  }
 }
diff --git a/apps/bff/src/main.ts b/apps/bff/src/main.ts
index f08a3bca..283f2d5d 100644
--- a/apps/bff/src/main.ts
+++ b/apps/bff/src/main.ts
@@ -1,3 +1,4 @@
+import "tsconfig-paths/register";
 import { Logger, type INestApplication } from "@nestjs/common";
 
 import { bootstrap } from "./app/bootstrap";
diff --git a/apps/bff/src/modules/invoices/invoices.controller.ts b/apps/bff/src/modules/invoices/invoices.controller.ts
index 360ccc32..cc57346e 100644
--- a/apps/bff/src/modules/invoices/invoices.controller.ts
+++ b/apps/bff/src/modules/invoices/invoices.controller.ts
@@ -173,10 +173,10 @@ export class InvoicesController {
   @ApiParam({ name: "id", type: Number, description: "Invoice ID" })
   @ApiOkResponse({ description: "List of related subscriptions" })
   @ApiResponse({ status: 404, description: "Invoice not found" })
-  async getInvoiceSubscriptions(
+  getInvoiceSubscriptions(
     @Request() req: AuthenticatedRequest,
     @Param("id", ParseIntPipe) invoiceId: number
-  ): Promise<Subscription[]> {
+  ): Subscription[] {
     if (invoiceId <= 0) {
       throw new BadRequestException("Invoice ID must be a positive number");
     }
diff --git a/apps/bff/src/modules/invoices/services/invoices-orchestrator.service.ts b/apps/bff/src/modules/invoices/services/invoices-orchestrator.service.ts
index 267f2e16..d3ded4ff 100644
--- a/apps/bff/src/modules/invoices/services/invoices-orchestrator.service.ts
+++ b/apps/bff/src/modules/invoices/services/invoices-orchestrator.service.ts
@@ -1,13 +1,6 @@
 import { Injectable, Inject } from "@nestjs/common";
 import { Logger } from "nestjs-pino";
-import {
-  Invoice,
-  InvoiceList,
-  InvoiceSsoLink,
-  InvoicePaymentLink,
-  PaymentMethodList,
-  PaymentGatewayList,
-} from "@customer-portal/domain";
+import { Invoice, InvoiceList } from "@customer-portal/domain";
 import { InvoiceRetrievalService } from "./invoice-retrieval.service";
 import { InvoiceHealthService } from "./invoice-health.service";
 import { InvoiceValidatorService } from "../validators/invoice-validator.service";
diff --git a/apps/bff/src/modules/subscriptions/sim-management.service.ts b/apps/bff/src/modules/subscriptions/sim-management.service.ts
index b63ab6b5..a1fc6bad 100644
--- a/apps/bff/src/modules/subscriptions/sim-management.service.ts
+++ b/apps/bff/src/modules/subscriptions/sim-management.service.ts
@@ -13,6 +13,7 @@ import type {
   SimTopUpHistoryRequest,
   SimFeaturesUpdateRequest,
 } from "./sim-management/types/sim-requests.types";
+import type { SimNotificationContext } from "./sim-management/interfaces/sim-base.interface";
 
 @Injectable()
 export class SimManagementService {
@@ -25,9 +26,9 @@ export class SimManagementService {
   private async notifySimAction(
     action: string,
     status: "SUCCESS" | "ERROR",
-    context: Record<string, unknown>
+    context: SimNotificationContext
   ): Promise<void> {
-    return this.simNotification.notifySimAction(action, status, context as any);
+    return this.simNotification.notifySimAction(action, status, context);
   }
 
   /**
diff --git a/apps/bff/src/modules/subscriptions/subscriptions.service.ts b/apps/bff/src/modules/subscriptions/subscriptions.service.ts
index 4b750f2d..89bd7aef 100644
--- a/apps/bff/src/modules/subscriptions/subscriptions.service.ts
+++ b/apps/bff/src/modules/subscriptions/subscriptions.service.ts
@@ -6,7 +6,7 @@ import { WhmcsService } from "@bff/integrations/whmcs/whmcs.service";
 import { MappingsService } from "@bff/modules/id-mappings/mappings.service";
 import { Logger } from "nestjs-pino";
 import { z } from "zod";
-import { subscriptionSchema } from "@customer-portal/domain/validation/shared/entities";
+import { subscriptionSchema } from "@customer-portal/domain";
 import type {
   WhmcsProduct,
   WhmcsProductsResponse,
diff --git a/apps/bff/tsconfig.build.json b/apps/bff/tsconfig.build.json
index b0b3023c..3796e8d6 100644
--- a/apps/bff/tsconfig.build.json
+++ b/apps/bff/tsconfig.build.json
@@ -13,7 +13,6 @@
   "include": ["src/**/*"],
   "exclude": ["node_modules", "dist", "test", "**/*.spec.ts"],
   "references": [
-    { "path": "../../packages/domain" },
-    { "path": "../../packages/validation" }
+    { "path": "../../packages/domain" }
   ]
 }
diff --git a/apps/portal/scripts/stubs/core-api.ts b/apps/portal/scripts/stubs/core-api.ts
index df6d3690..a21dca65 100644
--- a/apps/portal/scripts/stubs/core-api.ts
+++ b/apps/portal/scripts/stubs/core-api.ts
@@ -3,14 +3,14 @@ export type PostCall = [path: string, options?: unknown];
 export const postCalls: PostCall[] = [];
 
 export const apiClient = {
-  POST: async (path: string, options?: unknown) => {
+  POST: (path: string, options?: unknown) => {
     postCalls.push([path, options]);
-    return { data: null } as const;
+    return Promise.resolve({ data: null } as const);
   },
-  GET: async () => ({ data: null }) as const,
-  PUT: async () => ({ data: null }) as const,
-  PATCH: async () => ({ data: null }) as const,
-  DELETE: async () => ({ data: null }) as const,
+  GET: () => Promise.resolve({ data: null } as const),
+  PUT: () => Promise.resolve({ data: null } as const),
+  PATCH: () => Promise.resolve({ data: null } as const),
+  DELETE: () => Promise.resolve({ data: null } as const),
 };
 
 export const configureApiClientAuth = () => undefined;
diff --git a/apps/portal/scripts/test-request-password-reset.cjs b/apps/portal/scripts/test-request-password-reset.cjs
index 9f2e75b3..784cb2be 100755
--- a/apps/portal/scripts/test-request-password-reset.cjs
+++ b/apps/portal/scripts/test-request-password-reset.cjs
@@ -1,4 +1,6 @@
 #!/usr/bin/env node
+/* eslint-env node */
+/* global __dirname, console, process */
 
 const fs = require("node:fs");
 const path = require("node:path");
@@ -94,7 +96,7 @@ const { useAuthStore } = require("../src/features/auth/services/auth.store.ts");
     const [endpoint, options] = coreApiStub.postCalls[0];
     if (endpoint !== "/auth/request-password-reset") {
       throw new Error(
-        `Expected endpoint \"/auth/request-password-reset\" but received \"${endpoint}\"`
+        `Expected endpoint "/auth/request-password-reset" but received "${endpoint}"`
       );
     }
 
@@ -109,7 +111,7 @@ const { useAuthStore } = require("../src/features/auth/services/auth.store.ts");
 
     if (body.email !== payload.email) {
       throw new Error(
-        `Expected request body email to be \"${payload.email}\" but received \"${body.email}\"`
+        `Expected request body email to be "${payload.email}" but received "${body.email}"`
       );
     }
 
diff --git a/apps/portal/src/components/organisms/AppShell/Sidebar.tsx b/apps/portal/src/components/organisms/AppShell/Sidebar.tsx
index 5adc3ec9..2b2ab08b 100644
--- a/apps/portal/src/components/organisms/AppShell/Sidebar.tsx
+++ b/apps/portal/src/components/organisms/AppShell/Sidebar.tsx
@@ -140,10 +140,9 @@ const NavigationItem = memo(function NavigationItem({
                   href={child.href}
                   prefetch
                   onMouseEnter={() => {
-                    try {
-                      // Warm up code/data for faster clicks
-                      if (child.href) router.prefetch(child.href);
-                    } catch {}
+                    if (child.href) {
+                      void router.prefetch(child.href);
+                    }
                   }}
                   className={`group flex items-center px-3 py-2 text-sm rounded-md transition-all duration-200 relative ${
                     isChildActive
@@ -194,9 +193,9 @@ const NavigationItem = memo(function NavigationItem({
       href={item.href || "#"}
       prefetch
       onMouseEnter={() => {
-        try {
-          if (item.href && item.href !== "#") router.prefetch(item.href);
-        } catch {}
+        if (item.href && item.href !== "#") {
+          void router.prefetch(item.href);
+        }
       }}
       className={`group w-full flex items-center px-3 py-2.5 text-sm font-medium rounded-lg transition-all duration-200 relative ${
         isActive
diff --git a/apps/portal/src/features/account/hooks/useAddressEdit.ts b/apps/portal/src/features/account/hooks/useAddressEdit.ts
index e696b13e..ccd7b46e 100644
--- a/apps/portal/src/features/account/hooks/useAddressEdit.ts
+++ b/apps/portal/src/features/account/hooks/useAddressEdit.ts
@@ -11,12 +11,8 @@ import { useZodForm } from "@customer-portal/validation";
 
 export function useAddressEdit(initial: AddressFormData) {
   const handleSave = useCallback(async (formData: AddressFormData) => {
-    try {
-      const requestData = addressFormToRequest(formData);
-      await accountService.updateAddress(requestData);
-    } catch (error) {
-      throw error; // Let useZodForm handle the error state
-    }
+    const requestData = addressFormToRequest(formData);
+    await accountService.updateAddress(requestData);
   }, []);
 
   return useZodForm({
diff --git a/apps/portal/src/features/account/hooks/useProfileEdit.ts b/apps/portal/src/features/account/hooks/useProfileEdit.ts
index aa8539e8..32e9f043 100644
--- a/apps/portal/src/features/account/hooks/useProfileEdit.ts
+++ b/apps/portal/src/features/account/hooks/useProfileEdit.ts
@@ -12,17 +12,13 @@ import { useZodForm } from "@customer-portal/validation";
 
 export function useProfileEdit(initial: ProfileEditFormData) {
   const handleSave = useCallback(async (formData: ProfileEditFormData) => {
-    try {
-      const requestData = profileFormToRequest(formData);
-      const updated = await accountService.updateProfile(requestData);
+    const requestData = profileFormToRequest(formData);
+    const updated = await accountService.updateProfile(requestData);
 
-      useAuthStore.setState(state => ({
-        ...state,
-        user: state.user ? { ...state.user, ...updated } : state.user,
-      }));
-    } catch (error) {
-      throw error; // Let useZodForm handle the error state
-    }
+    useAuthStore.setState(state => ({
+      ...state,
+      user: state.user ? { ...state.user, ...updated } : state.user,
+    }));
   }, []);
 
   return useZodForm({
diff --git a/apps/portal/src/features/auth/components/LinkWhmcsForm/LinkWhmcsForm.tsx b/apps/portal/src/features/auth/components/LinkWhmcsForm/LinkWhmcsForm.tsx
index 2eb34c95..7317d7ce 100644
--- a/apps/portal/src/features/auth/components/LinkWhmcsForm/LinkWhmcsForm.tsx
+++ b/apps/portal/src/features/auth/components/LinkWhmcsForm/LinkWhmcsForm.tsx
@@ -22,17 +22,12 @@ export function LinkWhmcsForm({ onTransferred, className = "" }: LinkWhmcsFormPr
   const handleLink = useCallback(
     async (formData: LinkWhmcsFormData) => {
       clearError();
-      try {
-        const payload: LinkWhmcsRequestInput = {
-          email: formData.email,
-          password: formData.password,
-        };
-        const result = await linkWhmcs(payload);
-        onTransferred?.({ ...result, email: formData.email });
-      } catch (err) {
-        // Error is handled by useZodForm
-        throw err;
-      }
+      const payload: LinkWhmcsRequestInput = {
+        email: formData.email,
+        password: formData.password,
+      };
+      const result = await linkWhmcs(payload);
+      onTransferred?.({ ...result, email: formData.email });
     },
     [linkWhmcs, onTransferred, clearError]
   );
@@ -56,7 +51,7 @@ export function LinkWhmcsForm({ onTransferred, className = "" }: LinkWhmcsFormPr
           </p>
         </div>
 
-        <form onSubmit={handleSubmit} className="space-y-4">
+        <form onSubmit={event => void handleSubmit(event)} className="space-y-4">
           <FormField label="Email Address" error={errors.email} required>
             <Input
               type="email"
diff --git a/apps/portal/src/features/auth/components/LoginForm/LoginForm.tsx b/apps/portal/src/features/auth/components/LoginForm/LoginForm.tsx
index 6378951e..eae32597 100644
--- a/apps/portal/src/features/auth/components/LoginForm/LoginForm.tsx
+++ b/apps/portal/src/features/auth/components/LoginForm/LoginForm.tsx
@@ -10,7 +10,7 @@ import Link from "next/link";
 import { Button, Input, ErrorMessage } from "@/components/atoms";
 import { FormField } from "@/components/molecules/FormField/FormField";
 import { useLogin } from "../../hooks/use-auth";
-import { loginFormSchema, loginFormToRequest, type LoginFormData } from "@customer-portal/domain";
+import { loginFormSchema, loginFormToRequest } from "@customer-portal/domain";
 import { useZodForm } from "@customer-portal/validation";
 import { z } from "zod";
 
@@ -40,14 +40,14 @@ export function LoginForm({
   const handleLogin = useCallback(
     async ({ rememberMe: _rememberMe, ...formData }: LoginFormValues) => {
       clearError();
+      const requestData = loginFormToRequest(formData);
       try {
-        const requestData = loginFormToRequest(formData);
         await login(requestData);
         onSuccess?.();
       } catch (err) {
         const message = err instanceof Error ? err.message : "Login failed";
         onError?.(message);
-        throw err; // Re-throw to let useZodForm handle the error state
+        throw err;
       }
     },
     [login, onSuccess, onError, clearError]
@@ -61,7 +61,6 @@ export function LoginForm({
     setValue,
     setTouchedField,
     handleSubmit,
-    validateField,
   } = useZodForm<LoginFormValues>({
     schema: loginSchema,
     initialValues: {
@@ -74,7 +73,7 @@ export function LoginForm({
 
   return (
     <div className={`w-full max-w-md mx-auto ${className}`}>
-      <form onSubmit={handleSubmit} className="space-y-6">
+      <form onSubmit={event => void handleSubmit(event)} className="space-y-6">
         <FormField label="Email Address" error={touched.email ? errors.email : undefined} required>
           <Input
             type="email"
@@ -143,7 +142,7 @@ export function LoginForm({
         {showSignupLink && (
           <div className="text-center">
             <p className="text-sm text-gray-600">
-              Don't have an account?{" "}
+              Don&apos;t have an account?{" "}
               <Link
                 href="/auth/signup"
                 className="font-medium text-blue-600 hover:text-blue-500 transition-colors"
diff --git a/apps/portal/src/features/auth/components/PasswordResetForm/PasswordResetForm.tsx b/apps/portal/src/features/auth/components/PasswordResetForm/PasswordResetForm.tsx
index d0718dd2..03c1127e 100644
--- a/apps/portal/src/features/auth/components/PasswordResetForm/PasswordResetForm.tsx
+++ b/apps/portal/src/features/auth/components/PasswordResetForm/PasswordResetForm.tsx
@@ -49,6 +49,7 @@ export function PasswordResetForm({
       } catch (err) {
         const errorMessage = err instanceof Error ? err.message : "Request failed";
         onError?.(errorMessage);
+        throw err;
       }
     },
   });
@@ -80,6 +81,7 @@ export function PasswordResetForm({
       } catch (err) {
         const errorMessage = err instanceof Error ? err.message : "Reset failed";
         onError?.(errorMessage);
+        throw err;
       }
     },
   });
@@ -107,11 +109,11 @@ export function PasswordResetForm({
         <div className="text-center">
           <h2 className="text-2xl font-bold text-gray-900">Reset your password</h2>
           <p className="mt-2 text-sm text-gray-600">
-            Enter your email address and we'll send you a link to reset your password.
+            Enter your email address and we&apos;ll send you a link to reset your password.
           </p>
         </div>
 
-        <form onSubmit={requestForm.handleSubmit} className="space-y-4">
+        <form onSubmit={event => void requestForm.handleSubmit(event)} className="space-y-4">
           <FormField label="Email address" error={requestForm.errors.email} required>
             <Input
               type="email"
@@ -155,7 +157,7 @@ export function PasswordResetForm({
         <p className="mt-2 text-sm text-gray-600">Enter your new password below.</p>
       </div>
 
-      <form onSubmit={resetForm.handleSubmit} className="space-y-4">
+      <form onSubmit={event => void resetForm.handleSubmit(event)} className="space-y-4">
         <FormField label="New password" error={resetForm.errors.password} required>
           <Input
             type="password"
diff --git a/apps/portal/src/features/auth/components/SetPasswordForm/SetPasswordForm.tsx b/apps/portal/src/features/auth/components/SetPasswordForm/SetPasswordForm.tsx
index 1f96a700..ac5b9e91 100644
--- a/apps/portal/src/features/auth/components/SetPasswordForm/SetPasswordForm.tsx
+++ b/apps/portal/src/features/auth/components/SetPasswordForm/SetPasswordForm.tsx
@@ -62,6 +62,7 @@ export function SetPasswordForm({
       } catch (err) {
         const errorMessage = err instanceof Error ? err.message : "Failed to set password";
         onError?.(errorMessage);
+        throw err;
       }
     },
   });
@@ -89,7 +90,7 @@ export function SetPasswordForm({
         </p>
       </div>
 
-      <form onSubmit={form.handleSubmit} className="space-y-4">
+      <form onSubmit={event => void form.handleSubmit(event)} className="space-y-4">
         <FormField label="Email address" error={form.errors.email} required>
           <Input
             type="email"
diff --git a/apps/portal/src/features/auth/components/SignupForm/PasswordStep.tsx b/apps/portal/src/features/auth/components/SignupForm/PasswordStep.tsx
index 791d2e9d..8013a19a 100644
--- a/apps/portal/src/features/auth/components/SignupForm/PasswordStep.tsx
+++ b/apps/portal/src/features/auth/components/SignupForm/PasswordStep.tsx
@@ -10,11 +10,10 @@ import { FormField } from "@/components/molecules/FormField/FormField";
 import type { UseZodFormReturn } from "@customer-portal/validation";
 import type { SignupFormValues } from "./SignupForm";
 
-interface PasswordStepProps
-  extends Pick<
-    UseZodFormReturn<SignupFormValues>,
-    "values" | "errors" | "touched" | "setValue" | "setTouchedField"
-  > {}
+type PasswordStepProps = Pick<
+  UseZodFormReturn<SignupFormValues>,
+  "values" | "errors" | "touched" | "setValue" | "setTouchedField"
+>;
 
 export function PasswordStep({
   values,
diff --git a/apps/portal/src/features/auth/services/auth.store.ts b/apps/portal/src/features/auth/services/auth.store.ts
index 3064d22a..4fff470d 100644
--- a/apps/portal/src/features/auth/services/auth.store.ts
+++ b/apps/portal/src/features/auth/services/auth.store.ts
@@ -319,8 +319,10 @@ export const useAuthStore = create<AuthState>()(
           set({ user: profile });
         } catch (error) {
           // Token might be expired, try to refresh
-          handleAuthError(error, get().logout);
-          await get().refreshTokens();
+          const shouldLogout = handleAuthError(error, get().logout);
+          if (!shouldLogout) {
+            await get().refreshTokens();
+          }
         }
       },
 
@@ -328,7 +330,7 @@ export const useAuthStore = create<AuthState>()(
         const { tokens } = get();
         if (!tokens?.refreshToken) {
           // No refresh token available, logout
-          get().logout();
+          await get().logout();
           return;
         }
 
@@ -349,7 +351,10 @@ export const useAuthStore = create<AuthState>()(
           set({ tokens: newTokens, isAuthenticated: true });
         } catch (error) {
           // Refresh failed, logout
-          handleAuthError(error, get().logout);
+          const shouldLogout = handleAuthError(error, get().logout);
+          if (!shouldLogout) {
+            await get().logout();
+          }
         }
       },
 
diff --git a/apps/portal/src/features/billing/views/PaymentMethods.tsx b/apps/portal/src/features/billing/views/PaymentMethods.tsx
index 04679df8..23762971 100644
--- a/apps/portal/src/features/billing/views/PaymentMethods.tsx
+++ b/apps/portal/src/features/billing/views/PaymentMethods.tsx
@@ -7,7 +7,7 @@ import { SubCard } from "@/components/molecules/SubCard/SubCard";
 import { useSession } from "@/features/auth/hooks";
 import { useAuthStore } from "@/features/auth/services/auth.store";
 
-import { apiClient, getDataOrThrow } from "@/lib/api";
+import { apiClient, getDataOrThrow, isApiError } from "@/lib/api";
 import { openSsoLink } from "@/features/billing/utils/sso";
 import { usePaymentRefresh } from "@/features/billing/hooks/usePaymentRefresh";
 import { PaymentMethodCard, usePaymentMethods } from "@/features/billing";
@@ -62,9 +62,9 @@ export function PaymentMethodsContainer() {
       });
       const sso = getDataOrThrow<InvoiceSsoLink>(response, "Failed to open payment methods portal");
       openSsoLink(sso.url, { newTab: true });
-    } catch (err) {
+    } catch (err: unknown) {
       logger.error(err, "Failed to open payment methods");
-      if (err && typeof err === "object" && "status" in err && (err as any).status === 401) {
+      if (isApiError(err) && err.response.status === 401) {
         setError("Authentication failed. Please log in again.");
       } else {
         setError("Unable to access payment methods. Please try again later.");
diff --git a/apps/portal/src/features/catalog/components/internet/configure/steps/ServiceConfigurationStep.tsx b/apps/portal/src/features/catalog/components/internet/configure/steps/ServiceConfigurationStep.tsx
index d7c8d7b7..c48da8be 100644
--- a/apps/portal/src/features/catalog/components/internet/configure/steps/ServiceConfigurationStep.tsx
+++ b/apps/portal/src/features/catalog/components/internet/configure/steps/ServiceConfigurationStep.tsx
@@ -46,8 +46,8 @@ export function ServiceConfigurationStep({ plan, mode, setMode, isTransitioning,
             from our tech team for details.
           </p>
           <p className="text-xs mt-2">
-            * Will appear on the invoice as "Platinum Base Plan". Device subscriptions will be added
-            later.
+            * Will appear on the invoice as &quot;Platinum Base Plan&quot;. Device subscriptions will be
+            added later.
           </p>
         </AlertBanner>
       )}
diff --git a/apps/portal/src/features/catalog/hooks/useSimConfigure.ts b/apps/portal/src/features/catalog/hooks/useSimConfigure.ts
index 88b86647..22eb6ad8 100644
--- a/apps/portal/src/features/catalog/hooks/useSimConfigure.ts
+++ b/apps/portal/src/features/catalog/hooks/useSimConfigure.ts
@@ -93,8 +93,7 @@ export function useSimConfigure(planId?: string): UseSimConfigureResult {
   const { values, errors, setValue, validate } = useZodForm<SimConfigureFormData>({
     schema: simConfigureFormSchema,
     initialValues,
-    onSubmit: async data => {
-      // This hook doesn't submit directly, just validates
+    onSubmit: data => {
       simConfigureFormToRequest(data);
     },
   });
@@ -120,7 +119,7 @@ export function useSimConfigure(planId?: string): UseSimConfigureResult {
   // Initialize from URL params
   useEffect(() => {
     let mounted = true;
-    async function initializeFromParams() {
+    const initializeFromParams = () => {
       if (simLoading || !simData) return;
 
       if (mounted) {
@@ -136,9 +135,9 @@ export function useSimConfigure(planId?: string): UseSimConfigureResult {
         setScheduledActivationDate(searchParams.get("scheduledDate") || "");
         setWantsMnp(searchParams.get("wantsMnp") === "true");
       }
-    }
+    };
 
-    void initializeFromParams();
+    initializeFromParams();
     return () => {
       mounted = false;
     };
@@ -173,25 +172,37 @@ export function useSimConfigure(planId?: string): UseSimConfigureResult {
 
     // Add addon pricing
     if (simData?.addons) {
-      values.selectedAddons.forEach((addonId: string) => {
+      values.selectedAddons.forEach(addonId => {
         const addon = simData.addons.find(a => a.id === addonId);
-        if (addon) {
-          if ((addon as any).billingType === "monthly") {
-            monthly += (addon as any).price || 0;
-          } else {
-            oneTime += (addon as any).price || 0;
-          }
+        if (!addon) return;
+
+        const billingType =
+          ("billingType" in addon && typeof (addon as { billingType?: string }).billingType === "string"
+            ? (addon as { billingType?: string }).billingType
+            : addon.billingCycle) ?? "";
+        const normalizedBilling = billingType.toLowerCase();
+        const recurringValue = addon.monthlyPrice ?? addon.unitPrice ?? 0;
+        const oneTimeValue = addon.oneTimePrice ?? addon.unitPrice ?? addon.monthlyPrice ?? 0;
+
+        if (normalizedBilling === "monthly") {
+          monthly += recurringValue;
+        } else {
+          oneTime += oneTimeValue;
         }
       });
     }
 
     // Add activation fees
     if (simData?.activationFees) {
-      const activationFee = simData.activationFees.find(
-        fee => (fee as any).simType === values.simType
-      );
+      const activationFee = simData.activationFees.find(fee => {
+        const rawSimType =
+          "simType" in fee && typeof (fee as { simType?: string }).simType === "string"
+            ? (fee as { simType?: string }).simType
+            : undefined;
+        return (rawSimType ?? fee.simPlanType) === values.simType;
+      });
       if (activationFee) {
-        oneTime += (activationFee as any).amount || 0;
+        oneTime += activationFee.oneTimePrice ?? activationFee.unitPrice ?? activationFee.monthlyPrice ?? 0;
       }
     }
 
diff --git a/apps/portal/src/features/orders/services/orders.service.ts b/apps/portal/src/features/orders/services/orders.service.ts
index 4cd25b4a..7d35df49 100644
--- a/apps/portal/src/features/orders/services/orders.service.ts
+++ b/apps/portal/src/features/orders/services/orders.service.ts
@@ -3,6 +3,14 @@ import type { CreateOrderRequest } from "@customer-portal/domain";
 
 const API_BASE = process.env.NEXT_PUBLIC_API_BASE || "http://localhost:4000";
 
+interface AuthStoreSnapshot {
+  state?: {
+    tokens?: {
+      accessToken?: unknown;
+    };
+  };
+}
+
 const getAuthHeader = (): string | undefined => {
   if (typeof window === "undefined") return undefined;
 
@@ -10,9 +18,9 @@ const getAuthHeader = (): string | undefined => {
   if (!authStore) return undefined;
 
   try {
-    const parsed = JSON.parse(authStore);
+    const parsed = JSON.parse(authStore) as AuthStoreSnapshot;
     const token = parsed?.state?.tokens?.accessToken;
-    return token ? `Bearer ${token}` : undefined;
+    return typeof token === "string" && token ? `Bearer ${token}` : undefined;
   } catch {
     return undefined;
   }
diff --git a/apps/portal/src/lib/api/index.ts b/apps/portal/src/lib/api/index.ts
index 5b807dc4..40759e4f 100644
--- a/apps/portal/src/lib/api/index.ts
+++ b/apps/portal/src/lib/api/index.ts
@@ -19,17 +19,17 @@ export const queryKeys = {
     session: () => ["auth", "session"] as const,
   },
   billing: {
-    invoices: (params?: Record<string, any>) => ["billing", "invoices", params] as const,
+    invoices: (params?: Record<string, unknown>) => ["billing", "invoices", params] as const,
     invoice: (id: string) => ["billing", "invoice", id] as const,
     paymentMethods: () => ["billing", "payment-methods"] as const,
   },
   subscriptions: {
     all: () => ["subscriptions"] as const,
-    list: (params?: Record<string, any>) => ["subscriptions", "list", params] as const,
+    list: (params?: Record<string, unknown>) => ["subscriptions", "list", params] as const,
     active: () => ["subscriptions", "active"] as const,
     stats: () => ["subscriptions", "stats"] as const,
     detail: (id: string) => ["subscriptions", "detail", id] as const,
-    invoices: (id: number, params?: Record<string, any>) =>
+    invoices: (id: number, params?: Record<string, unknown>) =>
       ["subscriptions", "invoices", id, params] as const,
   },
   dashboard: {
diff --git a/apps/portal/src/lib/api/runtime/client.ts b/apps/portal/src/lib/api/runtime/client.ts
index 8531544a..88248e09 100644
--- a/apps/portal/src/lib/api/runtime/client.ts
+++ b/apps/portal/src/lib/api/runtime/client.ts
@@ -85,6 +85,21 @@ export interface CreateClientOptions {
   handleError?: (response: Response) => void | Promise<void>;
 }
 
+const getBodyMessage = (body: unknown): string | null => {
+  if (typeof body === "string") {
+    return body;
+  }
+
+  if (typeof body === "object" && body !== null && "message" in body) {
+    const maybeMessage = (body as { message?: unknown }).message;
+    if (typeof maybeMessage === "string") {
+      return maybeMessage;
+    }
+  }
+
+  return null;
+};
+
 async function defaultHandleError(response: Response) {
   if (response.ok) return;
 
@@ -96,13 +111,9 @@ async function defaultHandleError(response: Response) {
     const contentType = cloned.headers.get("content-type");
     if (contentType?.includes("application/json")) {
       body = await cloned.json();
-      if (
-        body &&
-        typeof body === "object" &&
-        "message" in body &&
-        typeof (body as any).message === "string"
-      ) {
-        message = (body as any).message;
+      const jsonMessage = getBodyMessage(body);
+      if (jsonMessage) {
+        message = jsonMessage;
       }
     } else {
       const text = await cloned.text();
diff --git a/apps/portal/src/lib/hooks/useLocalStorage.ts b/apps/portal/src/lib/hooks/useLocalStorage.ts
index 760fb74d..51194b78 100644
--- a/apps/portal/src/lib/hooks/useLocalStorage.ts
+++ b/apps/portal/src/lib/hooks/useLocalStorage.ts
@@ -26,7 +26,8 @@ export function useLocalStorage<T>(
     try {
       const item = window.localStorage.getItem(key);
       if (item) {
-        setStoredValue(JSON.parse(item));
+        const parsed: unknown = JSON.parse(item);
+        setStoredValue(parsed as T);
       }
     } catch (error) {
       logger.warn(
diff --git a/apps/portal/src/lib/utils/error-handling.ts b/apps/portal/src/lib/utils/error-handling.ts
index c7f628ce..f735e8c3 100644
--- a/apps/portal/src/lib/utils/error-handling.ts
+++ b/apps/portal/src/lib/utils/error-handling.ts
@@ -116,12 +116,15 @@ export function getUserFriendlyMessage(error: unknown): string {
 /**
  * Handle authentication errors consistently
  */
-export function handleAuthError(error: unknown, logout: () => void): void {
+export function handleAuthError(error: unknown, logout: () => void | Promise<void>): boolean {
   const errorInfo = getErrorInfo(error);
 
   if (errorInfo.shouldLogout) {
-    logout();
+    void logout();
+    return true;
   }
+
+  return false;
 }
 
 /**
diff --git a/packages/domain/tsconfig.json b/packages/domain/tsconfig.json
index 458aada3..af092737 100644
--- a/packages/domain/tsconfig.json
+++ b/packages/domain/tsconfig.json
@@ -1,8 +1,8 @@
 {
   "extends": "../../tsconfig.base.json",
   "compilerOptions": {
-    "module": "ESNext",
-    "moduleResolution": "bundler",
+    "module": "NodeNext",
+    "moduleResolution": "nodenext",
     "lib": ["ES2022"],
     "outDir": "./dist",
     "rootDir": "./src",