diff --git a/GdeiAssistant-iOS/Features/Auth/Repositories/MockAuthRepository.swift b/GdeiAssistant-iOS/Features/Auth/Repositories/MockAuthRepository.swift
index cd482f6..9e159fc 100644
--- a/GdeiAssistant-iOS/Features/Auth/Repositories/MockAuthRepository.swift
+++ b/GdeiAssistant-iOS/Features/Auth/Repositories/MockAuthRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockAuthRepository: AuthRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private let validUsername = "gdeiassistant"
     private let validPassword = "gdeiassistant"
 
diff --git a/GdeiAssistant-iOS/Features/Auth/ViewModels/LoginViewModel.swift b/GdeiAssistant-iOS/Features/Auth/ViewModels/LoginViewModel.swift
index 964d3b0..e3633db 100644
--- a/GdeiAssistant-iOS/Features/Auth/ViewModels/LoginViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Auth/ViewModels/LoginViewModel.swift
@@ -16,6 +16,10 @@ final class LoginViewModel: ObservableObject {
         self.authManager = authManager
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var currentDataSourceMode: DataSourceMode {
         authManager.currentDataSourceMode
     }
diff --git a/GdeiAssistant-iOS/Features/CET/Repositories/MockCETRepository.swift b/GdeiAssistant-iOS/Features/CET/Repositories/MockCETRepository.swift
index 9d8e302..60edea5 100644
--- a/GdeiAssistant-iOS/Features/CET/Repositories/MockCETRepository.swift
+++ b/GdeiAssistant-iOS/Features/CET/Repositories/MockCETRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockCETRepository: CETRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func fetchCaptchaImageBase64() async throws -> String {
         try await Task.sleep(nanoseconds: 120_000_000)
         return MockSeedData.cetCaptchaBase64
diff --git a/GdeiAssistant-iOS/Features/CET/ViewModels/CETViewModel.swift b/GdeiAssistant-iOS/Features/CET/ViewModels/CETViewModel.swift
index d0ea706..5849873 100644
--- a/GdeiAssistant-iOS/Features/CET/ViewModels/CETViewModel.swift
+++ b/GdeiAssistant-iOS/Features/CET/ViewModels/CETViewModel.swift
@@ -19,6 +19,10 @@ final class CETViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard dashboard == nil else { return }
         await refreshCaptcha()
diff --git a/GdeiAssistant-iOS/Features/Card/Repositories/MockCardRepository.swift b/GdeiAssistant-iOS/Features/Card/Repositories/MockCardRepository.swift
index d80ea02..cbfec2e 100644
--- a/GdeiAssistant-iOS/Features/Card/Repositories/MockCardRepository.swift
+++ b/GdeiAssistant-iOS/Features/Card/Repositories/MockCardRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockCardRepository: CardRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var isReportedLoss = false
 
     func fetchDashboard(on date: Date) async throws -> CampusCardDashboard {
diff --git a/GdeiAssistant-iOS/Features/Card/ViewModels/CardViewModel.swift b/GdeiAssistant-iOS/Features/Card/ViewModels/CardViewModel.swift
index d8e8637..9e6e540 100644
--- a/GdeiAssistant-iOS/Features/Card/ViewModels/CardViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Card/ViewModels/CardViewModel.swift
@@ -15,6 +15,10 @@ final class CardViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard dashboard == nil else { return }
         await loadDashboard()
diff --git a/GdeiAssistant-iOS/Features/Charge/Repositories/MockChargeRepository.swift b/GdeiAssistant-iOS/Features/Charge/Repositories/MockChargeRepository.swift
index 9b2a11d..3fbce7b 100644
--- a/GdeiAssistant-iOS/Features/Charge/Repositories/MockChargeRepository.swift
+++ b/GdeiAssistant-iOS/Features/Charge/Repositories/MockChargeRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockChargeRepository: ChargeRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func fetchCardInfo() async throws -> CampusCardDashboard {
         try await Task.sleep(for: .milliseconds(250))
         return CampusCardDashboard(
diff --git a/GdeiAssistant-iOS/Features/Charge/ViewModels/ChargeViewModel.swift b/GdeiAssistant-iOS/Features/Charge/ViewModels/ChargeViewModel.swift
index ce83040..b219bdc 100644
--- a/GdeiAssistant-iOS/Features/Charge/ViewModels/ChargeViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Charge/ViewModels/ChargeViewModel.swift
@@ -36,6 +36,10 @@ final class ChargeViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() {
         guard !hasLoaded else { return }
         hasLoaded = true
diff --git a/GdeiAssistant-iOS/Features/Collection/Repositories/MockCollectionRepository.swift b/GdeiAssistant-iOS/Features/Collection/Repositories/MockCollectionRepository.swift
index 124d22e..a3c7385 100644
--- a/GdeiAssistant-iOS/Features/Collection/Repositories/MockCollectionRepository.swift
+++ b/GdeiAssistant-iOS/Features/Collection/Repositories/MockCollectionRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockCollectionRepository: CollectionRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var borrowedBooks: [CollectionBorrowItem] = [
         CollectionBorrowItem(id: "c_borrow_1", sn: "sn_1001", code: "code_1001", title: "iOS 架构设计实践", author: "王磊", borrowDate: "2026-03-01", returnDate: "2026-03-22", renewCount: 0),
         CollectionBorrowItem(id: "c_borrow_2", sn: "sn_1002", code: "code_1002", title: "数据库系统概论", author: "陈小华", borrowDate: "2026-02-24", returnDate: "2026-03-17", renewCount: 1)
diff --git a/GdeiAssistant-iOS/Features/Collection/ViewModels/CollectionViewModel.swift b/GdeiAssistant-iOS/Features/Collection/ViewModels/CollectionViewModel.swift
index 1cd31b8..717d10c 100644
--- a/GdeiAssistant-iOS/Features/Collection/ViewModels/CollectionViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Collection/ViewModels/CollectionViewModel.swift
@@ -22,6 +22,10 @@ final class CollectionViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func search() async {
         let trimmed = FormValidationSupport.trimmed(keyword)
         guard !trimmed.isEmpty else {
diff --git a/GdeiAssistant-iOS/Features/Community/Repositories/MockCommunityRepository.swift b/GdeiAssistant-iOS/Features/Community/Repositories/MockCommunityRepository.swift
index 464382e..1772b50 100644
--- a/GdeiAssistant-iOS/Features/Community/Repositories/MockCommunityRepository.swift
+++ b/GdeiAssistant-iOS/Features/Community/Repositories/MockCommunityRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockCommunityRepository: CommunityRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var likeCountOverrides: [String: Int] = [:]
     private var commentCountOverrides: [String: Int] = [:]
     private var addedComments: [String: [CommunityComment]] = [:]
diff --git a/GdeiAssistant-iOS/Features/Community/ViewModels/CommunityFeedViewModel.swift b/GdeiAssistant-iOS/Features/Community/ViewModels/CommunityFeedViewModel.swift
index 3bfa350..0330eea 100644
--- a/GdeiAssistant-iOS/Features/Community/ViewModels/CommunityFeedViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Community/ViewModels/CommunityFeedViewModel.swift
@@ -15,6 +15,10 @@ final class CommunityFeedViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard !hasLoaded else { return }
         await loadPosts()
diff --git a/GdeiAssistant-iOS/Features/Community/ViewModels/PostDetailViewModel.swift b/GdeiAssistant-iOS/Features/Community/ViewModels/PostDetailViewModel.swift
index 8fc4026..d9a270d 100644
--- a/GdeiAssistant-iOS/Features/Community/ViewModels/PostDetailViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Community/ViewModels/PostDetailViewModel.swift
@@ -19,6 +19,10 @@ final class PostDetailViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard detail == nil else { return }
         await loadDetail()
diff --git a/GdeiAssistant-iOS/Features/Community/ViewModels/TopicFeedViewModel.swift b/GdeiAssistant-iOS/Features/Community/ViewModels/TopicFeedViewModel.swift
index 344f9f4..fa646f0 100644
--- a/GdeiAssistant-iOS/Features/Community/ViewModels/TopicFeedViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Community/ViewModels/TopicFeedViewModel.swift
@@ -18,6 +18,10 @@ final class TopicFeedViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard topic == nil && posts.isEmpty else { return }
         await load()
diff --git a/GdeiAssistant-iOS/Features/DataCenter/Repositories/MockDataCenterRepository.swift b/GdeiAssistant-iOS/Features/DataCenter/Repositories/MockDataCenterRepository.swift
index 015d686..f61d92d 100644
--- a/GdeiAssistant-iOS/Features/DataCenter/Repositories/MockDataCenterRepository.swift
+++ b/GdeiAssistant-iOS/Features/DataCenter/Repositories/MockDataCenterRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockDataCenterRepository: DataCenterRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func queryElectricity(_ query: ElectricityQuery) async throws -> ElectricityBill {
         try await Task.sleep(nanoseconds: 180_000_000)
         guard FormValidationSupport.hasText(query.name), FormValidationSupport.hasText(query.studentNumber) else {
diff --git a/GdeiAssistant-iOS/Features/DataCenter/ViewModels/DataCenterViewModel.swift b/GdeiAssistant-iOS/Features/DataCenter/ViewModels/DataCenterViewModel.swift
index 8a7765d..b89bb5b 100644
--- a/GdeiAssistant-iOS/Features/DataCenter/ViewModels/DataCenterViewModel.swift
+++ b/GdeiAssistant-iOS/Features/DataCenter/ViewModels/DataCenterViewModel.swift
@@ -14,6 +14,10 @@ final class ElectricityFeesViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var availableYears: [Int] {
         ElectricityQuery.yearOptions
     }
@@ -53,6 +57,10 @@ final class YellowPageViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard categories.isEmpty else { return }
         await refresh()
diff --git a/GdeiAssistant-iOS/Features/Dating/Repositories/MockDatingRepository.swift b/GdeiAssistant-iOS/Features/Dating/Repositories/MockDatingRepository.swift
index dbbeac7..ec55912 100644
--- a/GdeiAssistant-iOS/Features/Dating/Repositories/MockDatingRepository.swift
+++ b/GdeiAssistant-iOS/Features/Dating/Repositories/MockDatingRepository.swift
@@ -14,6 +14,10 @@ final class MockDatingRepository: DatingRepository {
         myProfiles = Self.makeMyProfiles()
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func fetchProfiles(filter: DatingFilter) async throws -> [DatingProfile] {
         hallProfiles.filter { $0.area == filter.area }
     }
diff --git a/GdeiAssistant-iOS/Features/Dating/ViewModels/DatingViewModel.swift b/GdeiAssistant-iOS/Features/Dating/ViewModels/DatingViewModel.swift
index 94530d1..f33a692 100644
--- a/GdeiAssistant-iOS/Features/Dating/ViewModels/DatingViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Dating/ViewModels/DatingViewModel.swift
@@ -14,6 +14,10 @@ final class DatingHallViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard profiles.isEmpty else { return }
         await refresh()
@@ -66,6 +70,10 @@ final class DatingCenterViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadData() async {
         isLoading = true
         errorMessage = nil
@@ -126,6 +134,10 @@ final class PublishDatingViewModel: ObservableObject {
         self.profileRepository = profileRepository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var isFormValid: Bool {
         !nickname.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty &&
         selectedFaculty != ProfileFormSupport.unselectedOption &&
diff --git a/GdeiAssistant-iOS/Features/Delivery/Repositories/MockDeliveryRepository.swift b/GdeiAssistant-iOS/Features/Delivery/Repositories/MockDeliveryRepository.swift
index 863cea9..4fff580 100644
--- a/GdeiAssistant-iOS/Features/Delivery/Repositories/MockDeliveryRepository.swift
+++ b/GdeiAssistant-iOS/Features/Delivery/Repositories/MockDeliveryRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockDeliveryRepository: DeliveryRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var orders: [DeliveryOrder] = [
         DeliveryOrder(orderID: "delivery_001", displayName: "gdeiassistant", name: mockLocalizedText(simplifiedChinese: "代收", traditionalChinese: "代收", english: "Parcel pickup", japanese: "代理受取", korean: "대리수령"), pickupCode: "51233444567", contactPhone: "13800138000", price: 4.50, company: mockLocalizedText(simplifiedChinese: "菜鸟驿站", traditionalChinese: "菜鳥驛站", english: "Cainiao Station", japanese: "菜鳥ステーション", korean: "차이냐오 스테이션"), address: mockLocalizedText(simplifiedChinese: "南苑 3 栋 508", traditionalChinese: "南苑 3 棟 508", english: "South Court Bldg 3 Room 508", japanese: "南苑3棟508", korean: "남원 3동 508호"), state: .pending, remarks: mockLocalizedText(simplifiedChinese: "课后再送", traditionalChinese: "課後再送", english: "Deliver after class", japanese: "授業後にお願いします", korean: "수업 후 전달 부탁"), orderTime: mockLocalizedText(simplifiedChinese: "10分钟前", traditionalChinese: "10分鐘前", english: "10 min ago", japanese: "10分前", korean: "10분 전")),
         DeliveryOrder(orderID: "delivery_002", displayName: "20230018", name: mockLocalizedText(simplifiedChinese: "代收", traditionalChinese: "代收", english: "Parcel pickup", japanese: "代理受取", korean: "대리수령"), pickupCode: "40399881234", contactPhone: "13911112222", price: 6.00, company: mockLocalizedText(simplifiedChinese: "东门快递点", traditionalChinese: "東門快遞點", english: "East Gate Parcel Point", japanese: "東門宅配受取所", korean: "동문 택배 보관소"), address: mockLocalizedText(simplifiedChinese: "北苑 6 栋 203", traditionalChinese: "北苑 6 棟 203", english: "North Court Bldg 6 Room 203", japanese: "北苑6棟203", korean: "북원 6동 203호"), state: .delivering, remarks: mockLocalizedText(simplifiedChinese: "到宿舍楼下联系", traditionalChinese: "到宿舍樓下聯繫", english: "Message me when you arrive downstairs", japanese: "寮の下に着いたら連絡してください", korean: "기숙사 아래 도착하면 연락 주세요"), orderTime: mockLocalizedText(simplifiedChinese: "40分钟前", traditionalChinese: "40分鐘前", english: "40 min ago", japanese: "40分前", korean: "40분 전"))
diff --git a/GdeiAssistant-iOS/Features/Delivery/ViewModels/DeliveryViewModel.swift b/GdeiAssistant-iOS/Features/Delivery/ViewModels/DeliveryViewModel.swift
index c9ed89c..a1e644c 100644
--- a/GdeiAssistant-iOS/Features/Delivery/ViewModels/DeliveryViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Delivery/ViewModels/DeliveryViewModel.swift
@@ -16,6 +16,10 @@ final class DeliveryViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard orders.isEmpty else { return }
         await refresh()
@@ -78,6 +82,10 @@ final class PublishDeliveryViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var isFormValid: Bool {
         FormValidationSupport.hasText(pickupPlace) &&
         FormValidationSupport.hasText(phone) &&
diff --git a/GdeiAssistant-iOS/Features/Evaluate/Repositories/MockEvaluateRepository.swift b/GdeiAssistant-iOS/Features/Evaluate/Repositories/MockEvaluateRepository.swift
index 02fec49..97cc2c7 100644
--- a/GdeiAssistant-iOS/Features/Evaluate/Repositories/MockEvaluateRepository.swift
+++ b/GdeiAssistant-iOS/Features/Evaluate/Repositories/MockEvaluateRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockEvaluateRepository: EvaluateRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func submit(_ submission: EvaluateSubmission) async throws {
         try await Task.sleep(nanoseconds: 300_000_000)
         _ = submission
diff --git a/GdeiAssistant-iOS/Features/Evaluate/ViewModels/EvaluateViewModel.swift b/GdeiAssistant-iOS/Features/Evaluate/ViewModels/EvaluateViewModel.swift
index 0eff334..86e7005 100644
--- a/GdeiAssistant-iOS/Features/Evaluate/ViewModels/EvaluateViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Evaluate/ViewModels/EvaluateViewModel.swift
@@ -13,6 +13,10 @@ final class EvaluateViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func requestSubmit() {
         showConfirm = true
     }
diff --git a/GdeiAssistant-iOS/Features/Express/Repositories/MockExpressRepository.swift b/GdeiAssistant-iOS/Features/Express/Repositories/MockExpressRepository.swift
index 2f242ff..534b5f8 100644
--- a/GdeiAssistant-iOS/Features/Express/Repositories/MockExpressRepository.swift
+++ b/GdeiAssistant-iOS/Features/Express/Repositories/MockExpressRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockExpressRepository: ExpressRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var posts: [ExpressPost] = [
         ExpressPost(
             id: "express_001",
diff --git a/GdeiAssistant-iOS/Features/Express/ViewModels/ExpressViewModel.swift b/GdeiAssistant-iOS/Features/Express/ViewModels/ExpressViewModel.swift
index 7870cec..49d1145 100644
--- a/GdeiAssistant-iOS/Features/Express/ViewModels/ExpressViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Express/ViewModels/ExpressViewModel.swift
@@ -14,6 +14,10 @@ final class ExpressViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard posts.isEmpty else { return }
         await refresh()
@@ -93,6 +97,10 @@ final class PublishExpressViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var isFormValid: Bool {
         FormValidationSupport.hasText(nickname) &&
         FormValidationSupport.hasText(targetName) &&
diff --git a/GdeiAssistant-iOS/Features/Grade/Repositories/MockGradeRepository.swift b/GdeiAssistant-iOS/Features/Grade/Repositories/MockGradeRepository.swift
index 6b899ea..b4f775c 100644
--- a/GdeiAssistant-iOS/Features/Grade/Repositories/MockGradeRepository.swift
+++ b/GdeiAssistant-iOS/Features/Grade/Repositories/MockGradeRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockGradeRepository: GradeRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func fetchGrades(yearIndex: Int?) async throws -> GradeReport {
         try await Task.sleep(nanoseconds: 280_000_000)
         let index = yearIndex ?? 3
diff --git a/GdeiAssistant-iOS/Features/Grade/ViewModels/GradeViewModel.swift b/GdeiAssistant-iOS/Features/Grade/ViewModels/GradeViewModel.swift
index aadbe45..30ce060 100644
--- a/GdeiAssistant-iOS/Features/Grade/ViewModels/GradeViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Grade/ViewModels/GradeViewModel.swift
@@ -21,6 +21,10 @@ final class GradeViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         if report == nil {
             await loadGrades(yearIndex: Int(selectedYear))
diff --git a/GdeiAssistant-iOS/Features/GraduateExam/Repositories/MockGraduateExamRepository.swift b/GdeiAssistant-iOS/Features/GraduateExam/Repositories/MockGraduateExamRepository.swift
index dd3b55e..391e453 100644
--- a/GdeiAssistant-iOS/Features/GraduateExam/Repositories/MockGraduateExamRepository.swift
+++ b/GdeiAssistant-iOS/Features/GraduateExam/Repositories/MockGraduateExamRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockGraduateExamRepository: GraduateExamRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func queryScore(_ query: GraduateExamQuery) async throws -> GraduateExamScore {
         try await Task.sleep(nanoseconds: 180_000_000)
         guard FormValidationSupport.hasText(query.name), FormValidationSupport.hasText(query.examNumber), FormValidationSupport.hasText(query.idNumber) else {
diff --git a/GdeiAssistant-iOS/Features/GraduateExam/ViewModels/GraduateExamViewModel.swift b/GdeiAssistant-iOS/Features/GraduateExam/ViewModels/GraduateExamViewModel.swift
index 1011581..98b386d 100644
--- a/GdeiAssistant-iOS/Features/GraduateExam/ViewModels/GraduateExamViewModel.swift
+++ b/GdeiAssistant-iOS/Features/GraduateExam/ViewModels/GraduateExamViewModel.swift
@@ -14,6 +14,10 @@ final class GraduateExamViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func submit() async {
         guard FormValidationSupport.hasText(query.name), FormValidationSupport.hasText(query.examNumber), FormValidationSupport.hasText(query.idNumber) else {
             errorMessage = localizedString("graduateExam.formIncomplete")
diff --git a/GdeiAssistant-iOS/Features/Home/ViewModels/HomeViewModel.swift b/GdeiAssistant-iOS/Features/Home/ViewModels/HomeViewModel.swift
index ae77f58..d87425d 100644
--- a/GdeiAssistant-iOS/Features/Home/ViewModels/HomeViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Home/ViewModels/HomeViewModel.swift
@@ -17,6 +17,10 @@ final class HomeViewModel: ObservableObject {
         self.now = now
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         if loadedScheduleDay != Self.campusCalendar.startOfDay(for: now()) {
             await loadTodaySchedule()
diff --git a/GdeiAssistant-iOS/Features/Library/Repositories/MockLibraryRepository.swift b/GdeiAssistant-iOS/Features/Library/Repositories/MockLibraryRepository.swift
index d0f5ae8..52c6193 100644
--- a/GdeiAssistant-iOS/Features/Library/Repositories/MockLibraryRepository.swift
+++ b/GdeiAssistant-iOS/Features/Library/Repositories/MockLibraryRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockLibraryRepository: LibraryRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private let validPasswords: Set<String> = ["library123", "123456"]
     private var renewedRecordIDs: Set<String> = []
 
diff --git a/GdeiAssistant-iOS/Features/Library/ViewModels/LibraryViewModel.swift b/GdeiAssistant-iOS/Features/Library/ViewModels/LibraryViewModel.swift
index 4cdb1fe..e49d7e5 100644
--- a/GdeiAssistant-iOS/Features/Library/ViewModels/LibraryViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Library/ViewModels/LibraryViewModel.swift
@@ -21,6 +21,10 @@ final class LibraryViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         if books.isEmpty {
             await searchBooks()
diff --git a/GdeiAssistant-iOS/Features/LostFound/Repositories/MockLostFoundRepository.swift b/GdeiAssistant-iOS/Features/LostFound/Repositories/MockLostFoundRepository.swift
index 233b5e1..507dca4 100644
--- a/GdeiAssistant-iOS/Features/LostFound/Repositories/MockLostFoundRepository.swift
+++ b/GdeiAssistant-iOS/Features/LostFound/Repositories/MockLostFoundRepository.swift
@@ -9,6 +9,10 @@ final class MockLostFoundRepository: LostFoundRepository {
         seedPersonalItemsIfNeeded()
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func fetchItems() async throws -> [LostFoundItem] {
         try await Task.sleep(nanoseconds: 200_000_000)
         return items
diff --git a/GdeiAssistant-iOS/Features/LostFound/ViewModels/LostFoundViewModel.swift b/GdeiAssistant-iOS/Features/LostFound/ViewModels/LostFoundViewModel.swift
index 324eeef..a60a7df 100644
--- a/GdeiAssistant-iOS/Features/LostFound/ViewModels/LostFoundViewModel.swift
+++ b/GdeiAssistant-iOS/Features/LostFound/ViewModels/LostFoundViewModel.swift
@@ -13,6 +13,10 @@ final class LostFoundViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard items.isEmpty else { return }
         await refresh()
diff --git a/GdeiAssistant-iOS/Features/LostFound/ViewModels/PublishLostFoundViewModel.swift b/GdeiAssistant-iOS/Features/LostFound/ViewModels/PublishLostFoundViewModel.swift
index ca6556d..42919a0 100644
--- a/GdeiAssistant-iOS/Features/LostFound/ViewModels/PublishLostFoundViewModel.swift
+++ b/GdeiAssistant-iOS/Features/LostFound/ViewModels/PublishLostFoundViewModel.swift
@@ -3,6 +3,10 @@ import Combine
 
 @MainActor
 final class PublishLostFoundViewModel: ObservableObject {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     @Published var title = ""
     @Published var selectedType: LostFoundType = .lost
     @Published var selectedItemTypeID = 0
@@ -150,6 +154,10 @@ final class EditLostFoundViewModel: ObservableObject {
         phone = Self.extractContactValue(from: detail.contactHint, prefix: localizedString("lostFound.mapper.contactPhone")) ?? ""
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var itemTypeOptions: [String] {
         LostFoundRemoteMapper.itemTypes
     }
diff --git a/GdeiAssistant-iOS/Features/Marketplace/Repositories/MockMarketplaceRepository.swift b/GdeiAssistant-iOS/Features/Marketplace/Repositories/MockMarketplaceRepository.swift
index f910ebb..97fff7b 100644
--- a/GdeiAssistant-iOS/Features/Marketplace/Repositories/MockMarketplaceRepository.swift
+++ b/GdeiAssistant-iOS/Features/Marketplace/Repositories/MockMarketplaceRepository.swift
@@ -9,6 +9,10 @@ final class MockMarketplaceRepository: MarketplaceRepository {
         seedPersonalItemsIfNeeded()
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func fetchItems(typeID: Int?) async throws -> [MarketplaceItem] {
         try await Task.sleep(nanoseconds: 220_000_000)
         guard let typeID else {
diff --git a/GdeiAssistant-iOS/Features/Marketplace/ViewModels/MarketplaceViewModel.swift b/GdeiAssistant-iOS/Features/Marketplace/ViewModels/MarketplaceViewModel.swift
index 10724eb..52cd342 100644
--- a/GdeiAssistant-iOS/Features/Marketplace/ViewModels/MarketplaceViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Marketplace/ViewModels/MarketplaceViewModel.swift
@@ -15,6 +15,10 @@ final class MarketplaceViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var typeOptions: [(id: Int, title: String)] {
         MarketplaceRemoteMapper.itemTypes.enumerated().map { (id: $0.offset, title: $0.element) }
     }
diff --git a/GdeiAssistant-iOS/Features/Marketplace/ViewModels/PublishMarketplaceViewModel.swift b/GdeiAssistant-iOS/Features/Marketplace/ViewModels/PublishMarketplaceViewModel.swift
index 708625f..0ac6add 100644
--- a/GdeiAssistant-iOS/Features/Marketplace/ViewModels/PublishMarketplaceViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Marketplace/ViewModels/PublishMarketplaceViewModel.swift
@@ -3,6 +3,10 @@ import Combine
 
 @MainActor
 final class PublishMarketplaceViewModel: ObservableObject {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     @Published var title = ""
     @Published var priceText = ""
     @Published var descriptionText = ""
@@ -154,6 +158,10 @@ final class EditMarketplaceViewModel: ObservableObject {
         ) ?? ""
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var typeOptions: [String] {
         MarketplaceRemoteMapper.itemTypes
     }
diff --git a/GdeiAssistant-iOS/Features/Messages/Repositories/MockMessagesRepository.swift b/GdeiAssistant-iOS/Features/Messages/Repositories/MockMessagesRepository.swift
index 783072f..a4d5519 100644
--- a/GdeiAssistant-iOS/Features/Messages/Repositories/MockMessagesRepository.swift
+++ b/GdeiAssistant-iOS/Features/Messages/Repositories/MockMessagesRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockMessagesRepository: MessagesRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var announcementItems = MockFactory.makeNotifications().filter { $0.destination == .announcement }
     private var interactionItems = MockFactory.makeNotifications().filter(\.isInteractionItem)
     private let announcementDetailsByID = MockFactory.makeAnnouncementDetailsByID()
diff --git a/GdeiAssistant-iOS/Features/Messages/ViewModels/InteractionMessageListViewModel.swift b/GdeiAssistant-iOS/Features/Messages/ViewModels/InteractionMessageListViewModel.swift
index 0a2e6bb..7b809d4 100644
--- a/GdeiAssistant-iOS/Features/Messages/ViewModels/InteractionMessageListViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Messages/ViewModels/InteractionMessageListViewModel.swift
@@ -19,6 +19,10 @@ final class InteractionMessageListViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard items.isEmpty else { return }
         await refresh()
diff --git a/GdeiAssistant-iOS/Features/Messages/ViewModels/MessagesViewModel.swift b/GdeiAssistant-iOS/Features/Messages/ViewModels/MessagesViewModel.swift
index 9b90bca..ae6d9b9 100644
--- a/GdeiAssistant-iOS/Features/Messages/ViewModels/MessagesViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Messages/ViewModels/MessagesViewModel.swift
@@ -30,6 +30,10 @@ final class MessagesViewModel: ObservableObject {
         self.messagesRepository = messagesRepository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var isInitialLoading: Bool {
         if hasAnyContent {
             return false
diff --git a/GdeiAssistant-iOS/Features/Messages/ViewModels/SystemNoticeListViewModel.swift b/GdeiAssistant-iOS/Features/Messages/ViewModels/SystemNoticeListViewModel.swift
index 7d8e359..db80a42 100644
--- a/GdeiAssistant-iOS/Features/Messages/ViewModels/SystemNoticeListViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Messages/ViewModels/SystemNoticeListViewModel.swift
@@ -18,6 +18,10 @@ final class SystemNoticeListViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard items.isEmpty else { return }
         await refresh()
diff --git a/GdeiAssistant-iOS/Features/News/Repositories/MockNewsRepository.swift b/GdeiAssistant-iOS/Features/News/Repositories/MockNewsRepository.swift
index 1aaf487..887affd 100644
--- a/GdeiAssistant-iOS/Features/News/Repositories/MockNewsRepository.swift
+++ b/GdeiAssistant-iOS/Features/News/Repositories/MockNewsRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockNewsRepository: NewsRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private let items = [
         NewsItem(id: "news_1", type: 1, title: "学校高质量发展大会暨 2026 年工作会议召开", publishDate: "2026-03-03", content: "学校召开高质量发展大会，系统总结上一阶段重点工作，并部署年度改革发展任务。", sourceURL: "https://www.gdei.edu.cn/1324/1001.htm"),
         NewsItem(id: "news_2", type: 2, title: "管理学院召开教职工思想教育会议", publishDate: "2026-03-19", content: "管理学院围绕师德师风建设与年度重点工作召开专题会议。", sourceURL: "https://www.gdei.edu.cn/1325/2001.htm"),
diff --git a/GdeiAssistant-iOS/Features/News/ViewModels/NewsViewModel.swift b/GdeiAssistant-iOS/Features/News/ViewModels/NewsViewModel.swift
index bd01fc2..dcdabf2 100644
--- a/GdeiAssistant-iOS/Features/News/ViewModels/NewsViewModel.swift
+++ b/GdeiAssistant-iOS/Features/News/ViewModels/NewsViewModel.swift
@@ -18,6 +18,10 @@ final class NewsViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard items.isEmpty else { return }
         await refresh()
diff --git a/GdeiAssistant-iOS/Features/Photograph/Repositories/MockPhotographRepository.swift b/GdeiAssistant-iOS/Features/Photograph/Repositories/MockPhotographRepository.swift
index cd0a4c7..d5d6c59 100644
--- a/GdeiAssistant-iOS/Features/Photograph/Repositories/MockPhotographRepository.swift
+++ b/GdeiAssistant-iOS/Features/Photograph/Repositories/MockPhotographRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockPhotographRepository: PhotographRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var posts: [PhotographPost] = MockPhotographRepository.makeInitialPosts()
 
     private var comments: [String: [PhotographCommentItem]] = MockPhotographRepository.makeInitialComments()
diff --git a/GdeiAssistant-iOS/Features/Photograph/ViewModels/PhotographViewModel.swift b/GdeiAssistant-iOS/Features/Photograph/ViewModels/PhotographViewModel.swift
index fe48c95..c84281e 100644
--- a/GdeiAssistant-iOS/Features/Photograph/ViewModels/PhotographViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Photograph/ViewModels/PhotographViewModel.swift
@@ -19,6 +19,10 @@ final class PhotographViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard posts.isEmpty else { return }
         await refresh()
@@ -113,6 +117,10 @@ final class PublishPhotographViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var isFormValid: Bool {
         FormValidationSupport.hasText(title) && !images.isEmpty && images.count <= 4
     }
diff --git a/GdeiAssistant-iOS/Features/Profile/Repositories/MockAccountCenterRepository.swift b/GdeiAssistant-iOS/Features/Profile/Repositories/MockAccountCenterRepository.swift
index 0c87812..8c64403 100644
--- a/GdeiAssistant-iOS/Features/Profile/Repositories/MockAccountCenterRepository.swift
+++ b/GdeiAssistant-iOS/Features/Profile/Repositories/MockAccountCenterRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockAccountCenterRepository: AccountCenterRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var privacySettings = PrivacySettings.default
     private var phoneStatus = ContactBindingStatus(
         isBound: true,
diff --git a/GdeiAssistant-iOS/Features/Profile/ViewModels/CampusCredentialViewModel.swift b/GdeiAssistant-iOS/Features/Profile/ViewModels/CampusCredentialViewModel.swift
index c7d1435..f29ba4e 100644
--- a/GdeiAssistant-iOS/Features/Profile/ViewModels/CampusCredentialViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Profile/ViewModels/CampusCredentialViewModel.swift
@@ -15,6 +15,10 @@ final class CampusCredentialViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var canRunAction: Bool {
         !isLoading && !isActionRunning
     }
diff --git a/GdeiAssistant-iOS/Features/Profile/ViewModels/PrivacySettingsViewModel.swift b/GdeiAssistant-iOS/Features/Profile/ViewModels/PrivacySettingsViewModel.swift
index 1fbe1d7..e63e3f6 100644
--- a/GdeiAssistant-iOS/Features/Profile/ViewModels/PrivacySettingsViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Profile/ViewModels/PrivacySettingsViewModel.swift
@@ -15,6 +15,10 @@ final class PrivacySettingsViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func load() async {
         isLoading = true
         errorMessage = nil
diff --git a/GdeiAssistant-iOS/Features/Profile/ViewModels/SecurityCenterViewModels.swift b/GdeiAssistant-iOS/Features/Profile/ViewModels/SecurityCenterViewModels.swift
index 1bc65d6..7bac319 100644
--- a/GdeiAssistant-iOS/Features/Profile/ViewModels/SecurityCenterViewModels.swift
+++ b/GdeiAssistant-iOS/Features/Profile/ViewModels/SecurityCenterViewModels.swift
@@ -13,6 +13,10 @@ final class LoginRecordViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func load() async {
         isLoading = true
         errorMessage = nil
diff --git a/GdeiAssistant-iOS/Features/Profile/ViewModels/SettingsViewModel.swift b/GdeiAssistant-iOS/Features/Profile/ViewModels/SettingsViewModel.swift
index 7121d3a..22b481e 100644
--- a/GdeiAssistant-iOS/Features/Profile/ViewModels/SettingsViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Profile/ViewModels/SettingsViewModel.swift
@@ -13,6 +13,10 @@ final class SettingsViewModel: ObservableObject {
         self.preferences = preferences
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var isDebug: Bool {
         environment.isDebug
     }
diff --git a/GdeiAssistant-iOS/Features/Profile/ViewModels/SupportCenterViewModels.swift b/GdeiAssistant-iOS/Features/Profile/ViewModels/SupportCenterViewModels.swift
index b723248..1353337 100644
--- a/GdeiAssistant-iOS/Features/Profile/ViewModels/SupportCenterViewModels.swift
+++ b/GdeiAssistant-iOS/Features/Profile/ViewModels/SupportCenterViewModels.swift
@@ -23,6 +23,10 @@ final class FeedbackViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var isFormValid: Bool {
         FormValidationSupport.hasText(content)
     }
@@ -61,6 +65,10 @@ final class DownloadDataViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func load() async {
         isLoading = true
         errorMessage = nil
@@ -109,6 +117,10 @@ final class AvatarEditViewModel: ObservableObject {
         self.sessionState = sessionState
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func load() async {
         isLoading = true
         defer { isLoading = false }
@@ -173,6 +185,10 @@ final class DeleteAccountViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var canSubmit: Bool {
         agreed && FormValidationSupport.hasText(password)
     }
diff --git a/GdeiAssistant-iOS/Features/Schedule/Repositories/MockScheduleRepository.swift b/GdeiAssistant-iOS/Features/Schedule/Repositories/MockScheduleRepository.swift
index 0f6d5b2..5f30912 100644
--- a/GdeiAssistant-iOS/Features/Schedule/Repositories/MockScheduleRepository.swift
+++ b/GdeiAssistant-iOS/Features/Schedule/Repositories/MockScheduleRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockScheduleRepository: ScheduleRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func fetchWeeklySchedule(weekIndex: Int) async throws -> WeeklySchedule {
         try await Task.sleep(nanoseconds: 300_000_000)
         return MockFactory.makeWeeklySchedule(weekIndex: weekIndex)
diff --git a/GdeiAssistant-iOS/Features/Schedule/ViewModels/ScheduleViewModel.swift b/GdeiAssistant-iOS/Features/Schedule/ViewModels/ScheduleViewModel.swift
index 5e086e8..cbefe2f 100644
--- a/GdeiAssistant-iOS/Features/Schedule/ViewModels/ScheduleViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Schedule/ViewModels/ScheduleViewModel.swift
@@ -16,6 +16,10 @@ final class ScheduleViewModel: ObservableObject {
         self.selectedWeekIndex = initialWeekIndex
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var todayCourses: [CourseItem] {
         guard let schedule else { return [] }
         let weekday = Calendar.current.component(.weekday, from: Date())
diff --git a/GdeiAssistant-iOS/Features/Secret/Repositories/MockSecretRepository.swift b/GdeiAssistant-iOS/Features/Secret/Repositories/MockSecretRepository.swift
index 8100674..78eab8e 100644
--- a/GdeiAssistant-iOS/Features/Secret/Repositories/MockSecretRepository.swift
+++ b/GdeiAssistant-iOS/Features/Secret/Repositories/MockSecretRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockSecretRepository: SecretRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var posts = MockFactory.makeSecretPosts()
     private var detailsByID = MockFactory.makeSecretDetailsByID()
 
diff --git a/GdeiAssistant-iOS/Features/Secret/ViewModels/PublishSecretViewModel.swift b/GdeiAssistant-iOS/Features/Secret/ViewModels/PublishSecretViewModel.swift
index 73ad2df..7bad169 100644
--- a/GdeiAssistant-iOS/Features/Secret/ViewModels/PublishSecretViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Secret/ViewModels/PublishSecretViewModel.swift
@@ -3,6 +3,10 @@ import Combine
 
 @MainActor
 final class PublishSecretViewModel: ObservableObject {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     @Published var mode: SecretDraftMode = .text
     @Published var selectedThemeID = Int.random(in: 1...12)
     @Published var content = ""
diff --git a/GdeiAssistant-iOS/Features/Secret/ViewModels/SecretViewModel.swift b/GdeiAssistant-iOS/Features/Secret/ViewModels/SecretViewModel.swift
index 0686499..debe62a 100644
--- a/GdeiAssistant-iOS/Features/Secret/ViewModels/SecretViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Secret/ViewModels/SecretViewModel.swift
@@ -17,6 +17,10 @@ final class SecretViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard posts.isEmpty else { return }
         await refresh()
diff --git a/GdeiAssistant-iOS/Features/Social/Repositories/MockSocialRepository.swift b/GdeiAssistant-iOS/Features/Social/Repositories/MockSocialRepository.swift
index cb2f14a..7494beb 100644
--- a/GdeiAssistant-iOS/Features/Social/Repositories/MockSocialRepository.swift
+++ b/GdeiAssistant-iOS/Features/Social/Repositories/MockSocialRepository.swift
@@ -189,6 +189,10 @@ final class MockSocialRepository: SocialRepository {
         return page(items, cursor: cursor, limit: limit)
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func fetchConversation(id: String) async throws -> ConversationSummary {
         try await delay()
         guard let conversation = conversations[id] else {
diff --git a/GdeiAssistant-iOS/Features/Social/ViewModels/ChatThreadViewModel.swift b/GdeiAssistant-iOS/Features/Social/ViewModels/ChatThreadViewModel.swift
index e768172..c13e2f6 100644
--- a/GdeiAssistant-iOS/Features/Social/ViewModels/ChatThreadViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Social/ViewModels/ChatThreadViewModel.swift
@@ -43,6 +43,10 @@ final class ChatThreadViewModel: ObservableObject {
         self.tokenProvider = tokenProvider
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var currentUserID: String? {
         resolvedCurrentUserID
     }
diff --git a/GdeiAssistant-iOS/Features/Social/ViewModels/ConversationListViewModel.swift b/GdeiAssistant-iOS/Features/Social/ViewModels/ConversationListViewModel.swift
index b79aa2f..702b5aa 100644
--- a/GdeiAssistant-iOS/Features/Social/ViewModels/ConversationListViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Social/ViewModels/ConversationListViewModel.swift
@@ -20,6 +20,10 @@ final class ConversationListViewModel: ObservableObject {
         self.realtimeManager = realtimeManager
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func start() async {
         await reload()
         startPolling()
diff --git a/GdeiAssistant-iOS/Features/Social/ViewModels/DirectMessagePrivacyViewModel.swift b/GdeiAssistant-iOS/Features/Social/ViewModels/DirectMessagePrivacyViewModel.swift
index 0a36b7a..50cce73 100644
--- a/GdeiAssistant-iOS/Features/Social/ViewModels/DirectMessagePrivacyViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Social/ViewModels/DirectMessagePrivacyViewModel.swift
@@ -15,6 +15,10 @@ final class DirectMessagePrivacyViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func load() async {
         isLoading = true
         errorMessage = nil
diff --git a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialBlockListViewModel.swift b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialBlockListViewModel.swift
index 0d7e699..6a18911 100644
--- a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialBlockListViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialBlockListViewModel.swift
@@ -15,6 +15,10 @@ final class SocialBlockListViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func reload() async {
         isLoading = true
         errorMessage = nil
diff --git a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialMeSummaryViewModel.swift b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialMeSummaryViewModel.swift
index 52a15d5..285f484 100644
--- a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialMeSummaryViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialMeSummaryViewModel.swift
@@ -13,6 +13,10 @@ final class SocialMeSummaryViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func load() async {
         isLoading = true
         errorMessage = nil
diff --git a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialPublicProfileViewModel.swift b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialPublicProfileViewModel.swift
index e655f9d..61a4fd9 100644
--- a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialPublicProfileViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialPublicProfileViewModel.swift
@@ -18,6 +18,10 @@ final class SocialPublicProfileViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func load() async {
         isLoading = true
         errorMessage = nil
diff --git a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialRelationshipListViewModel.swift b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialRelationshipListViewModel.swift
index badade1..882e51f 100644
--- a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialRelationshipListViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialRelationshipListViewModel.swift
@@ -19,6 +19,10 @@ final class SocialRelationshipListViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func reload() async {
         isLoading = true
         errorMessage = nil
diff --git a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialUserSearchViewModel.swift b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialUserSearchViewModel.swift
index 219b12f..ccaab59 100644
--- a/GdeiAssistant-iOS/Features/Social/ViewModels/SocialUserSearchViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Social/ViewModels/SocialUserSearchViewModel.swift
@@ -18,6 +18,10 @@ final class SocialUserSearchViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func search() {
         searchTask?.cancel()
         searchTask = Task {
diff --git a/GdeiAssistant-iOS/Features/Spare/Repositories/MockSpareRepository.swift b/GdeiAssistant-iOS/Features/Spare/Repositories/MockSpareRepository.swift
index a53d5d5..e93999c 100644
--- a/GdeiAssistant-iOS/Features/Spare/Repositories/MockSpareRepository.swift
+++ b/GdeiAssistant-iOS/Features/Spare/Repositories/MockSpareRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockSpareRepository: SpareRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func queryRooms(_ query: SpareQuery) async throws -> [SpareRoomItem] {
         try await Task.sleep(nanoseconds: 180_000_000)
         _ = query
diff --git a/GdeiAssistant-iOS/Features/Spare/ViewModels/SpareViewModel.swift b/GdeiAssistant-iOS/Features/Spare/ViewModels/SpareViewModel.swift
index c0a4b16..dafe6e6 100644
--- a/GdeiAssistant-iOS/Features/Spare/ViewModels/SpareViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Spare/ViewModels/SpareViewModel.swift
@@ -14,6 +14,10 @@ final class SpareViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func submitQuery() async {
         isLoading = true
         errorMessage = nil
diff --git a/GdeiAssistant-iOS/Features/Topic/Repositories/MockTopicRepository.swift b/GdeiAssistant-iOS/Features/Topic/Repositories/MockTopicRepository.swift
index 9eefb10..107c3c7 100644
--- a/GdeiAssistant-iOS/Features/Topic/Repositories/MockTopicRepository.swift
+++ b/GdeiAssistant-iOS/Features/Topic/Repositories/MockTopicRepository.swift
@@ -2,6 +2,10 @@ import Foundation
 
 @MainActor
 final class MockTopicRepository: TopicRepository {
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     private var posts: [TopicPost] = [
         TopicPost(
             id: "topic_001",
diff --git a/GdeiAssistant-iOS/Features/Topic/ViewModels/TopicViewModel.swift b/GdeiAssistant-iOS/Features/Topic/ViewModels/TopicViewModel.swift
index 2b4c966..d769971 100644
--- a/GdeiAssistant-iOS/Features/Topic/ViewModels/TopicViewModel.swift
+++ b/GdeiAssistant-iOS/Features/Topic/ViewModels/TopicViewModel.swift
@@ -15,6 +15,10 @@ final class TopicViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     func loadIfNeeded() async {
         guard posts.isEmpty else { return }
         await refresh()
@@ -87,6 +91,10 @@ final class PublishTopicViewModel: ObservableObject {
         self.repository = repository
     }
 
+    // No actor-bound cleanup. Avoid the iOS 26.2 MainActor isolated-deinit
+    // back-deployment crash on synchronous release (swiftlang/swift#87316).
+    nonisolated deinit {}
+
     var isFormValid: Bool {
         FormValidationSupport.hasText(topic) && FormValidationSupport.hasText(content) && content.count <= 250 && images.count <= 9
     }
diff --git a/GdeiAssistant-iOSTests/Container/AppContainerBootstrapTests.swift b/GdeiAssistant-iOSTests/Container/AppContainerBootstrapTests.swift
index 1cd2a87..8b6a39f 100644
--- a/GdeiAssistant-iOSTests/Container/AppContainerBootstrapTests.swift
+++ b/GdeiAssistant-iOSTests/Container/AppContainerBootstrapTests.swift
@@ -297,6 +297,22 @@ final class AppContainerBootstrapTests: XCTestCase {
         )
     }
 
+    func testMarketplaceTypesDeclareNonisolatedDeinitAgainstMainActorBackDeployCrash() throws {
+        let expectations = [
+            "GdeiAssistant-iOS/Features/Marketplace/ViewModels/MarketplaceViewModel.swift",
+            "GdeiAssistant-iOS/Features/Marketplace/ViewModels/PublishMarketplaceViewModel.swift",
+            "GdeiAssistant-iOS/Features/Marketplace/Repositories/MockMarketplaceRepository.swift"
+        ]
+
+        for path in expectations {
+            let source = try sourceFileContents(at: path)
+            XCTAssertTrue(
+                source.contains("nonisolated deinit"),
+                "\(path) must declare nonisolated deinit to avoid the iOS 26.2 MainActor isolated-deinit crash (swiftlang/swift#87316)."
+            )
+        }
+    }
+
     private func sourceFileContents(at relativePath: String) throws -> String {
         let url = URL(fileURLWithPath: #filePath)
             .deletingLastPathComponent()
diff --git a/GdeiAssistant-iOSTests/Marketplace/MarketplaceViewModelTests.swift b/GdeiAssistant-iOSTests/Marketplace/MarketplaceViewModelTests.swift
index e334cec..9bfd410 100644
--- a/GdeiAssistant-iOSTests/Marketplace/MarketplaceViewModelTests.swift
+++ b/GdeiAssistant-iOSTests/Marketplace/MarketplaceViewModelTests.swift
@@ -4,7 +4,13 @@ import XCTest
 @MainActor
 final class MarketplaceViewModelTests: XCTestCase {
 
-    func testInitialStateIsEmpty() async {
+    /// Sync construction used to crash the runner with
+    /// `malloc: pointer being freed was not allocated` under
+    /// `SWIFT_DEFAULT_ACTOR_ISOLATION = MainActor` (iOS 26.2 MainActor
+    /// isolated-deinit back-deployment, swiftlang/swift#87316). The root
+    /// fix is `nonisolated deinit` on `MarketplaceViewModel` and
+    /// `MockMarketplaceRepository`; this sync case stays as a regression probe.
+    func testInitialStateIsEmpty() {
         let vm = MarketplaceViewModel(repository: MockMarketplaceRepository())
 
         XCTAssertTrue(vm.items.isEmpty)
@@ -12,6 +18,17 @@ final class MarketplaceViewModelTests: XCTestCase {
         XCTAssertNil(vm.errorMessage)
     }
 
+    func testViewModelAndMockRepositoryReleaseSynchronouslyWithoutCrash() {
+        for _ in 0..<20 {
+            var vm: MarketplaceViewModel? = MarketplaceViewModel(
+                repository: MockMarketplaceRepository()
+            )
+            weak var weakVM = vm
+            vm = nil
+            XCTAssertNil(weakVM)
+        }
+    }
+
     func testLoadIfNeededPopulatesItems() async {
         let vm = MarketplaceViewModel(repository: MockMarketplaceRepository())