diff --git a/README.md b/README.md
index b09bc76b..afcd2440 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,7 @@ which enables developers to delivery best-in-class iOS and Android commerce
 experiences.
 
 - [Platform Requirements](#platform-requirements)
+- [Version Compatibility](#version-compatibility)
 - [Getting Started](#getting-started)
   - [1. Installation](#1-installation)
   - [2. Minimum Android requirements](#2-minimum-android-requirements)
@@ -64,10 +65,24 @@ experiences.
 
 ## Platform Requirements
 
-- **React Native** - Minimum version `0.70`
+- **React Native** - Minimum version `0.76` (v4+) / `0.70` (v3 and earlier)
 - **iOS** - Minimum version iOS 13
 - **Android** - Minimum Java 11 & Android SDK version `23`
 
+## Version Compatibility
+
+Starting with **v4.0.0**, `@shopify/checkout-sheet-kit` requires the React Native
+**New Architecture** (TurboModules + Fabric). Apps on the old architecture must
+stay on the `v3.x` line until they migrate.
+
+| Package version | React Native   | Architecture       |
+| --------------- | -------------- | ------------------ |
+| `4.x`           | `>= 0.76`      | New Architecture   |
+| `3.x`           | `>= 0.70`      | Old Architecture   |
+
+See the [React Native upgrade guide](https://reactnative.dev/docs/the-new-architecture/use-the-new-architecture)
+for help enabling the New Architecture in your app.
+
 ## Getting Started
 
 Shopify Checkout Kit is an open-source NPM package.
diff --git a/dev.yml b/dev.yml
index fdd13738..1abbf7d5 100644
--- a/dev.yml
+++ b/dev.yml
@@ -10,7 +10,7 @@ up:
       - sccache
   - ruby
   - xcode:
-      version: "26.2"
+      version: '26.2'
       runtimes:
         ios:
           - version: 23C54 # 26.2
diff --git a/modules/@shopify/checkout-sheet-kit/package.json b/modules/@shopify/checkout-sheet-kit/package.json
index 522d60d2..c1347ba8 100644
--- a/modules/@shopify/checkout-sheet-kit/package.json
+++ b/modules/@shopify/checkout-sheet-kit/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@shopify/checkout-sheet-kit",
   "license": "MIT",
-  "version": "3.8.0",
+  "version": "4.0.0",
   "main": "lib/commonjs/index.js",
   "types": "src/index.ts",
   "source": "src/index.ts",
diff --git a/sample/ios/Podfile.lock b/sample/ios/Podfile.lock
index e730f3a9..07faf199 100644
--- a/sample/ios/Podfile.lock
+++ b/sample/ios/Podfile.lock
@@ -2578,7 +2578,7 @@ PODS:
     - ReactCommon/turbomodule/core
     - SocketRocket
     - Yoga
-  - RNShopifyCheckoutSheetKit (3.8.0):
+  - RNShopifyCheckoutSheetKit (4.0.0):
     - boost
     - DoubleConversion
     - fast_float
@@ -2996,7 +2996,7 @@ SPEC CHECKSUMS:
   RNGestureHandler: eeb622199ef1fb3a076243131095df1c797072f0
   RNReanimated: 237d420b7bb4378ef1dacc7d7a5c674fddb4b5d2
   RNScreens: 3fc29af06302e1f1c18a7829fe57cbc2c0259912
-  RNShopifyCheckoutSheetKit: 0da44f403a7176465fd25aa58c6fe9edfc95353b
+  RNShopifyCheckoutSheetKit: 2a8c97d7780466538843d4cb1368c7ed76a33689
   RNVectorIcons: be4d047a76ad307ffe54732208fb0498fcb8477f
   ShopifyCheckoutSheetKit: 5253ca4da4c4f31069286509693930d02b4150d8
   SocketRocket: d4aabe649be1e368d1318fdf28a022d714d65748