diff --git a/Sources/ProcessOut/Sources/Core/Extensions/UIImage+Dynamic.swift b/Sources/ProcessOut/Sources/Core/Extensions/UIImage+Dynamic.swift
index ca5969e16..2e68d34da 100644
--- a/Sources/ProcessOut/Sources/Core/Extensions/UIImage+Dynamic.swift
+++ b/Sources/ProcessOut/Sources/Core/Extensions/UIImage+Dynamic.swift
@@ -9,9 +9,9 @@ import UIKit
 
 extension UIImage {
 
+    @MainActor
     static func dynamic(lightImage: UIImage?, darkImage: UIImage?) -> UIImage? {
-        assert(Thread.isMainThread)
-        // When image with scale greater than 3 is registed asset created explicitly produced image
+        // When image with scale greater than 3 is registered asset created explicitly produced image
         // is malformed and doesn't contain images for light nor dark styles.
         guard let image = lightImage ?? darkImage else {
             return nil
diff --git a/Sources/ProcessOutCoreUI/Sources/Backports/OnSubmit/View+OnSubmit.swift b/Sources/ProcessOutCoreUI/Sources/Backports/OnSubmit/View+OnSubmit.swift
index 16d97b214..2a9d6a3aa 100644
--- a/Sources/ProcessOutCoreUI/Sources/Backports/OnSubmit/View+OnSubmit.swift
+++ b/Sources/ProcessOutCoreUI/Sources/Backports/OnSubmit/View+OnSubmit.swift
@@ -10,7 +10,7 @@ import SwiftUI
 extension POBackport where Wrapped: Any {
 
     @MainActor
-    final class SubmitAction: Sendable {
+    struct SubmitAction: Sendable {
 
         typealias Action = () -> Void // swiftlint:disable:this nesting
 
@@ -22,7 +22,7 @@ extension POBackport where Wrapped: Any {
             actions.forEach { $0() }
         }
 
-        func append(action: @escaping Action) {
+        mutating func append(action: @escaping Action) {
             actions.append(action)
         }
 
diff --git a/Sources/ProcessOutUI/Sources/Modules/DynamicCheckout/Interactor/DynamicCheckout/DynamicCheckoutDefaultInteractor.swift b/Sources/ProcessOutUI/Sources/Modules/DynamicCheckout/Interactor/DynamicCheckout/DynamicCheckoutDefaultInteractor.swift
index f5db2ed92..c8854910c 100644
--- a/Sources/ProcessOutUI/Sources/Modules/DynamicCheckout/Interactor/DynamicCheckout/DynamicCheckoutDefaultInteractor.swift
+++ b/Sources/ProcessOutUI/Sources/Modules/DynamicCheckout/Interactor/DynamicCheckout/DynamicCheckoutDefaultInteractor.swift
@@ -707,8 +707,8 @@ final class DynamicCheckoutDefaultInteractor:
 
     // MARK: - Events
 
+    @MainActor
     private func send(event: PODynamicCheckoutEvent) {
-        assert(Thread.isMainThread, "Method should be called on main thread.")
         logger.debug("Did send event: '\(event)'")
         delegate?.dynamicCheckout(didEmitEvent: event)
     }
diff --git a/Sources/ProcessOutUI/Sources/Modules/DynamicCheckout/Sessions/PassKit/DynamicCheckoutPassKitPaymentDefaultSession.swift b/Sources/ProcessOutUI/Sources/Modules/DynamicCheckout/Sessions/PassKit/DynamicCheckoutPassKitPaymentDefaultSession.swift
index d3dafad82..dfe27d0a5 100644
--- a/Sources/ProcessOutUI/Sources/Modules/DynamicCheckout/Sessions/PassKit/DynamicCheckoutPassKitPaymentDefaultSession.swift
+++ b/Sources/ProcessOutUI/Sources/Modules/DynamicCheckout/Sessions/PassKit/DynamicCheckoutPassKitPaymentDefaultSession.swift
@@ -55,7 +55,7 @@ extension DynamicCheckoutPassKitPaymentDefaultSession: POPassKitPaymentAuthoriza
 
     func paymentAuthorizationControllerDidFinish(_ controller: POPassKitPaymentAuthorizationController) {
         guard let didFinishContinuation else {
-            preconditionFailure("Continue must be set.")
+            preconditionFailure("Continuation must be set.")
         }
         didFinishContinuation.resume()
     }
diff --git a/Sources/ProcessOutUI/Sources/Modules/NativeAlternativePayment/Interactor/NativeAlternativePaymentDefaultInteractor.swift b/Sources/ProcessOutUI/Sources/Modules/NativeAlternativePayment/Interactor/NativeAlternativePaymentDefaultInteractor.swift
index c53011ae3..52f387ac4 100644
--- a/Sources/ProcessOutUI/Sources/Modules/NativeAlternativePayment/Interactor/NativeAlternativePaymentDefaultInteractor.swift
+++ b/Sources/ProcessOutUI/Sources/Modules/NativeAlternativePayment/Interactor/NativeAlternativePaymentDefaultInteractor.swift
@@ -403,8 +403,8 @@ final class NativeAlternativePaymentDefaultInteractor:
 
     // MARK: - Events
 
+    @MainActor
     private func send(event: PONativeAlternativePaymentEvent) {
-        assert(Thread.isMainThread, "Method should be called on main thread.")
         logger.debug("Did send event: '\(event)'")
         delegate?.nativeAlternativePaymentDidEmitEvent(event)
     }
@@ -513,7 +513,7 @@ final class NativeAlternativePaymentDefaultInteractor:
                 switch parameter.specification.type {
                 case .singleSelect:
                     let availableValues = parameter.specification.availableValues?.map(\.value) ?? []
-                    precondition(availableValues.contains(value), "Unknown `singleSelect` parameter value.")
+                    assert(availableValues.contains(value), "Unknown `singleSelect` parameter value.")
                     defaultValue = value
                 default:
                     defaultValue = parameter.formatter?.string(for: value) ?? value