diff --git a/lib/data/repositories/quote_repository.dart b/lib/data/repositories/quote_repository.dart
index 4fa91cf7e..5406a9800 100644
--- a/lib/data/repositories/quote_repository.dart
+++ b/lib/data/repositories/quote_repository.dart
@@ -1,4 +1,5 @@
 // Dart imports:
+import 'dart:async';
 import 'dart:convert';
 import 'dart:core';
 
@@ -31,8 +32,9 @@ class QuoteRepository {
         credentials.token);
 
     final InvoiceItemResponse quoteResponse = await (compute<dynamic, dynamic>(
-        SerializationUtils.deserializeWith,
-        <dynamic>[InvoiceItemResponse.serializer, response]) as FutureOr<InvoiceItemResponse>);
+            SerializationUtils.deserializeWith,
+            <dynamic>[InvoiceItemResponse.serializer, response])
+        as FutureOr<InvoiceItemResponse>);
 
     return quoteResponse.data;
   }
@@ -49,8 +51,9 @@ class QuoteRepository {
     final dynamic response = await webClient.get(url, credentials.token);
 
     final InvoiceListResponse quoteResponse = await (compute<dynamic, dynamic>(
-        SerializationUtils.deserializeWith,
-        <dynamic>[InvoiceListResponse.serializer, response]) as FutureOr<InvoiceListResponse>);
+            SerializationUtils.deserializeWith,
+            <dynamic>[InvoiceListResponse.serializer, response])
+        as FutureOr<InvoiceListResponse>);
 
     return quoteResponse.data;
   }
diff --git a/lib/data/repositories/recurring_invoice_repository.dart b/lib/data/repositories/recurring_invoice_repository.dart
index e03ec69a1..509c498da 100644
--- a/lib/data/repositories/recurring_invoice_repository.dart
+++ b/lib/data/repositories/recurring_invoice_repository.dart
@@ -51,7 +51,7 @@ class RecurringInvoiceRepository {
 
   Future<List<InvoiceEntity>> bulkAction(
       Credentials credentials, List<String> ids, EntityAction action,
-      {Map<String, Object?>? data}) async {
+      {Map<String, Object>? data}) async {
     if (ids.length > kMaxEntitiesPerBulkAction && action.applyMaxLimit) {
       ids = ids.sublist(0, kMaxEntitiesPerBulkAction);
     }
diff --git a/lib/data/repositories/task_repository.dart b/lib/data/repositories/task_repository.dart
index 10d25f060..e3ff9e02c 100644
--- a/lib/data/repositories/task_repository.dart
+++ b/lib/data/repositories/task_repository.dart
@@ -1,4 +1,5 @@
 // Dart imports:
+import 'dart:async';
 import 'dart:convert';
 import 'dart:core';
 
@@ -29,8 +30,9 @@ class TaskRepository {
         '${credentials.url}/tasks/$entityId', credentials.token);
 
     final TaskItemResponse taskResponse = await (compute<dynamic, dynamic>(
-        SerializationUtils.deserializeWith,
-        <dynamic>[TaskItemResponse.serializer, response]) as FutureOr<TaskItemResponse>);
+            SerializationUtils.deserializeWith,
+            <dynamic>[TaskItemResponse.serializer, response])
+        as FutureOr<TaskItemResponse>);
 
     return taskResponse.data;
   }
@@ -49,8 +51,9 @@ class TaskRepository {
     final dynamic response = await webClient.get(url, credentials.token);
 
     final TaskListResponse taskResponse = await (compute<dynamic, dynamic>(
-        SerializationUtils.deserializeWith,
-        <dynamic>[TaskListResponse.serializer, response]) as FutureOr<TaskListResponse>);
+            SerializationUtils.deserializeWith,
+            <dynamic>[TaskListResponse.serializer, response])
+        as FutureOr<TaskListResponse>);
 
     return taskResponse.data;
   }
diff --git a/lib/data/repositories/vendor_repository.dart b/lib/data/repositories/vendor_repository.dart
index 4667168a4..682ac4a8a 100644
--- a/lib/data/repositories/vendor_repository.dart
+++ b/lib/data/repositories/vendor_repository.dart
@@ -1,4 +1,5 @@
 // Dart imports:
+import 'dart:async';
 import 'dart:convert';
 import 'dart:core';
 
@@ -31,8 +32,9 @@ class VendorRepository {
         credentials.token);
 
     final VendorItemResponse vendorResponse = await (compute<dynamic, dynamic>(
-        SerializationUtils.deserializeWith,
-        <dynamic>[VendorItemResponse.serializer, response]) as FutureOr<VendorItemResponse>);
+            SerializationUtils.deserializeWith,
+            <dynamic>[VendorItemResponse.serializer, response])
+        as FutureOr<VendorItemResponse>);
 
     return vendorResponse.data;
   }
@@ -45,8 +47,9 @@ class VendorRepository {
     final dynamic response = await webClient.get(url, credentials.token);
 
     final VendorListResponse vendorResponse = await (compute<dynamic, dynamic>(
-        SerializationUtils.deserializeWith,
-        <dynamic>[VendorListResponse.serializer, response]) as FutureOr<VendorListResponse>);
+            SerializationUtils.deserializeWith,
+            <dynamic>[VendorListResponse.serializer, response])
+        as FutureOr<VendorListResponse>);
 
     return vendorResponse.data;
   }
diff --git a/lib/redux/app/app_middleware.dart b/lib/redux/app/app_middleware.dart
index f574c7c27..5aa390ef4 100644
--- a/lib/redux/app/app_middleware.dart
+++ b/lib/redux/app/app_middleware.dart
@@ -234,10 +234,10 @@ Middleware<AppState> _createLoadState(
       store.dispatch(LoadStateSuccess(appState));
       store.dispatch(RefreshData(
           completer: Completer<Null>()
-            ..future.then((value) {
+            ..future.then<Null>(() {
               AppBuilder.of(navigatorKey.currentContext!)!.rebuild();
               store.dispatch(UpdatedSetting());
-            } as FutureOr<_> Function(Null))));
+            } as FutureOr<Null> Function(Null))));
 
       if (uiState!.currentRoute != LoginScreen.route &&
           uiState!.currentRoute.isNotEmpty) {
diff --git a/lib/redux/app/app_state.dart b/lib/redux/app/app_state.dart
index 772bf965a..ffe71c2cb 100644
--- a/lib/redux/app/app_state.dart
+++ b/lib/redux/app/app_state.dart
@@ -106,7 +106,9 @@ abstract class AppState implements Built<AppState, AppStateBuilder> {
               .map((index) => UserCompanyState(reportErrors))
               .toList()),
       uiState: UIState(
-          currentRoute: currentRoute, sortFields: prefState?.sortFields),
+          currentRoute: currentRoute,
+          sortFields: prefState?.sortFields ??
+              BuiltMap<EntityType, PrefStateSortField>()),
       prefState: prefState ?? PrefState(),
     );
   }
@@ -192,7 +194,8 @@ abstract class AppState implements Built<AppState, AppStateBuilder> {
     return color.isNotEmpty;
   }
 
-  bool get showReviewApp => !prefState.hideReviewApp && company!.daysActive > 60;
+  bool get showReviewApp =>
+      !prefState.hideReviewApp && company!.daysActive > 60;
 
   bool get showOneYearReviewApp =>
       !prefState.hideOneYearReviewApp && company!.daysActive > 365;
@@ -251,7 +254,8 @@ abstract class AppState implements Built<AppState, AppStateBuilder> {
   List<HistoryRecord> get unfilteredHistoryList =>
       prefState.companyPrefs[company!.id]!.historyList.toList();
 
-  bool? shouldSelectEntity({EntityType? entityType, List<String?>? entityList}) {
+  bool? shouldSelectEntity(
+      {EntityType? entityType, List<String?>? entityList}) {
     final entityUIState = getUIState(entityType);
 
     if (prefState.isMobile ||
@@ -962,11 +966,11 @@ abstract class AppState implements Built<AppState, AppStateBuilder> {
         : timeago.format(convertTimestampToDate(
             (userCompanyState.lastUpdated / 1000).round()));
 
-    final staticUpdated =
-        staticState.updatedAt == null || staticState.updatedAt == 0
-            ? 'Blank'
-            : timeago.format(
-                convertTimestampToDate((staticState.updatedAt! / 1000).round()));
+    final staticUpdated = staticState.updatedAt == null ||
+            staticState.updatedAt == 0
+        ? 'Blank'
+        : timeago.format(
+            convertTimestampToDate((staticState.updatedAt! / 1000).round()));
 
     final passwordUpdated = authState.lastEnteredPasswordAt == null ||
             authState.lastEnteredPasswordAt == 0
diff --git a/lib/redux/auth/auth_middleware.dart b/lib/redux/auth/auth_middleware.dart
index dfdc4ad97..99368e47d 100644
--- a/lib/redux/auth/auth_middleware.dart
+++ b/lib/redux/auth/auth_middleware.dart
@@ -379,7 +379,7 @@ Middleware<AppState> _createCompany(AuthRepository repository) {
       store.dispatch(RefreshData(
         allCompanies: true,
         completer: Completer<Null>()
-          ..future.then<Null>((_) {
+          ..future.then<Null>(() {
             store.dispatch(SelectCompany(companyIndex: state.companies.length));
             store.dispatch(ViewDashboard(force: true));
 
@@ -459,9 +459,9 @@ Middleware<AppState> _purgeData(AuthRepository repository) {
       store.dispatch(RefreshData(
           clearData: true,
           completer: Completer<Null>()
-            ..future.then((value) {
+            ..future.then<Null>(() {
               action.completer.complete(null);
-            } as FutureOr<_> Function(Null))));
+            } as FutureOr<Null> Function(Null))));
     }).catchError((Object error) {
       store.dispatch(PurgeDataFailure(error));
       action.completer.completeError(error);
diff --git a/lib/redux/company_gateway/company_gateway_actions.dart b/lib/redux/company_gateway/company_gateway_actions.dart
index 767361db1..175791879 100644
--- a/lib/redux/company_gateway/company_gateway_actions.dart
+++ b/lib/redux/company_gateway/company_gateway_actions.dart
@@ -309,9 +309,9 @@ void handleCompanyGatewayAction(BuildContext? context,
     case EntityAction.disconnect:
       final completer =
           snackBarCompleter<Null>(context, localization!.disconnectedGateway);
-      completer.future.then((value) {
+      completer.future.then<Null>(() {
         store.dispatch(RefreshData());
-      } as FutureOr<_> Function(Null));
+      } as FutureOr<Null> Function(Null));
       confirmCallback(
           context: context,
           callback: (_) {
diff --git a/lib/redux/dashboard/dashboard_reducer.dart b/lib/redux/dashboard/dashboard_reducer.dart
index 86abaf482..e864d9f41 100644
--- a/lib/redux/dashboard/dashboard_reducer.dart
+++ b/lib/redux/dashboard/dashboard_reducer.dart
@@ -60,7 +60,7 @@ DashboardUISettings dashboardSettingsReducer(
     } else if (action.includeTaxes != null) {
       return state.rebuild((b) => b..includeTaxes = action.includeTaxes);
     } else if (action.offset != null) {
-      return state.rebuild((b) => b..offset += action.offset!);
+      return state.rebuild((b) => b..offset = state.offset + action.offset!);
     } else if (action.currencyId != null) {
       return state.rebuild((b) => b..currencyId = action.currencyId);
     } else if (action.groupBy != null) {
diff --git a/lib/redux/dashboard/dashboard_selectors.dart b/lib/redux/dashboard/dashboard_selectors.dart
index 96dbcdb72..086f749e4 100644
--- a/lib/redux/dashboard/dashboard_selectors.dart
+++ b/lib/redux/dashboard/dashboard_selectors.dart
@@ -150,17 +150,18 @@ List<ChartDataGroup> _chartInvoices({
           outstandingData.entityMap[date] = [];
         }
 
-        totals[STATUS_ACTIVE]![date] += amount;
-        totals[STATUS_OUTSTANDING]![date] += balance;
+        totals[STATUS_ACTIVE]![date] = totals[STATUS_ACTIVE]![date]! + amount;
+        totals[STATUS_OUTSTANDING]![date] =
+            totals[STATUS_OUTSTANDING]![date]! + balance;
 
         activeData.periodTotal += amount;
         outstandingData.periodTotal += balance;
 
-        counts[STATUS_ACTIVE]++;
+        counts[STATUS_ACTIVE] = counts[STATUS_ACTIVE]! + 1;
         activeData.entityMap[date]!.add(invoice.id);
 
         if (invoice.balance > 0) {
-          counts[STATUS_OUTSTANDING]++;
+          counts[STATUS_OUTSTANDING] = counts[STATUS_OUTSTANDING]! + 1;
           outstandingData.entityMap[date]!.add(invoice.id);
         }
       }
@@ -275,7 +276,10 @@ List<ChartDataGroup> chartQuotes({
       }
     }
 
-    if (!quote.isSent || quote.isDeleted! || client.isDeleted! || date.isEmpty) {
+    if (!quote.isSent ||
+        quote.isDeleted! ||
+        client.isDeleted! ||
+        date.isEmpty) {
       // skip it
     } else if (!settings.matchesCurrency(client.currencyId)) {
       // skip it
@@ -312,18 +316,20 @@ List<ChartDataGroup> chartQuotes({
           unapprovedData.entityMap[date] = [];
         }
 
-        totals[STATUS_ACTIVE]![date] += amount;
-        counts[STATUS_ACTIVE]++;
+        totals[STATUS_ACTIVE]![date] = totals[STATUS_ACTIVE]![date]! + amount;
+        counts[STATUS_ACTIVE] = counts[STATUS_ACTIVE]! + 1;
         activeData.entityMap[date]!.add(quote.id);
 
         if (quote.isApproved) {
-          totals[STATUS_APPROVED]![date] += amount;
-          counts[STATUS_APPROVED]++;
+          totals[STATUS_APPROVED]![date] =
+              totals[STATUS_APPROVED]![date]! + amount;
+          counts[STATUS_APPROVED] = counts[STATUS_APPROVED]! + 1;
           approvedData.entityMap[date]!.add(quote.id);
           approvedData.periodTotal += amount;
         } else {
-          totals[STATUS_UNAPPROVED]![date] += amount;
-          counts[STATUS_UNAPPROVED]++;
+          totals[STATUS_UNAPPROVED]![date] =
+              totals[STATUS_UNAPPROVED]![date]! + amount;
+          counts[STATUS_UNAPPROVED] = counts[STATUS_UNAPPROVED]! + 1;
           unapprovedData.entityMap[date]!.add(quote.id);
           unapprovedData.periodTotal += amount;
         }
@@ -928,12 +934,13 @@ List<ChartDataGroup> chartExpenses(
   return data;
 }
 
-var memoizedChartExpenses = memo5((BuiltMap<String?, CurrencyEntity?> currencyMap,
-        CompanyEntity? company,
-        DashboardUISettings settings,
-        BuiltMap<String?, InvoiceEntity?> invoiceMap,
-        BuiltMap<String?, ExpenseEntity?> expenseMap) =>
-    chartExpenses(currencyMap, company!, settings, invoiceMap, expenseMap));
+var memoizedChartExpenses = memo5(
+    (BuiltMap<String?, CurrencyEntity?> currencyMap,
+            CompanyEntity? company,
+            DashboardUISettings settings,
+            BuiltMap<String?, InvoiceEntity?> invoiceMap,
+            BuiltMap<String?, ExpenseEntity?> expenseMap) =>
+        chartExpenses(currencyMap, company!, settings, invoiceMap, expenseMap));
 
 var memoizedPreviousChartExpenses = memo5(
     (BuiltMap<String?, CurrencyEntity?> currencyMap,
diff --git a/lib/ui/invoice/view/invoice_view_overview.dart b/lib/ui/invoice/view/invoice_view_overview.dart
index 7c4cb5140..b78caa474 100644
--- a/lib/ui/invoice/view/invoice_view_overview.dart
+++ b/lib/ui/invoice/view/invoice_view_overview.dart
@@ -189,14 +189,17 @@ class InvoiceOverview extends StatelessWidget {
         RecurringInvoiceFields.remainingCycles: invoice.remainingCycles == -1
             ? localization.endless
             : '${invoice.remainingCycles}',
-        RecurringInvoiceFields.autoBill: localization.lookup(invoice.autoBill)! +
-            ([SettingsEntity.AUTO_BILL_OPT_IN, SettingsEntity.AUTO_BILL_OPT_OUT]
-                    .contains(invoice.autoBill)
-                ? (' - ' +
-                    (invoice.autoBillEnabled
-                        ? localization.yes
-                        : localization.no))
-                : ''),
+        RecurringInvoiceFields.autoBill:
+            localization.lookup(invoice.autoBill)! +
+                ([
+                  SettingsEntity.AUTO_BILL_OPT_IN,
+                  SettingsEntity.AUTO_BILL_OPT_OUT
+                ].contains(invoice.autoBill)
+                    ? (' - ' +
+                        (invoice.autoBillEnabled
+                            ? localization.yes
+                            : localization.no))
+                    : ''),
         InvoiceFields.dueDate: invoice.dueDateDays == 'terms'
             ? localization.paymentTerm
             : invoice.dueDateDays == 'on_receipt'
@@ -320,12 +323,12 @@ class InvoiceOverview extends StatelessWidget {
       paymentMap.entries.forEach((entry) {
         final payment = entry.value!;
         final paymentable = entry.key;
-        String? amount = formatNumber(
+        String amount = formatNumber(
           paymentable.amount,
           context,
           clientId: invoice.isPurchaseOrder ? null : client!.id,
           vendorId: invoice.isPurchaseOrder ? invoice.vendorId : null,
-        );
+        )!;
         if (paymentable.amount != payment.amount) {
           amount += '/' +
               formatNumber(
@@ -350,12 +353,12 @@ class InvoiceOverview extends StatelessWidget {
       creditMap.entries.forEach((entry) {
         final credit = entry.value!;
         final paymentable = entry.key;
-        String? amount = formatNumber(
+        String amount = formatNumber(
           paymentable.amount,
           context,
           clientId: invoice.isPurchaseOrder ? null : client!.id,
           vendorId: invoice.isPurchaseOrder ? invoice.vendorId : null,
-        );
+        )!;
         if (paymentable.amount != credit.amount) {
           amount += '/' +
               formatNumber(