new file: core/uniffi/bindings/android/Cryptec.java

new file:   core/uniffi/bindings/ios/Cryptec.h
	new file:   mobile/__tests__/nativeModuleIntegration.test.ts
	new file:   mobile/android/src/main/java/com/cryptec/CryptecModule.java
	new file:   mobile/android/src/main/java/com/cryptec/CryptecPackage.java
	new file:   mobile/ios/CryptecModule.m

core/uniffi/bindings/android/Cryptec.java

@@ -0,0 +1,10 @@
+// UniFFI-generated placeholder for Android (stub).
+// The real generated class will provide JNI hooks to the Rust library.
+package org.cryptec.uniffi.bindings;
+
+public final class Cryptec {
+    public static String generate_mnemonic(int strength) { return ""; }
+    public static String first_receive_address(String mnemonic) { return ""; }
+    public static String create_psbt(String mnemonic, String to, long sats) { return ""; }
+    public static String sign_psbt(String mnemonic, String psbt_b64) { return ""; }
+}

core/uniffi/bindings/ios/Cryptec.h

@@ -0,0 +1,15 @@
+// UniFFI placeholder header (iOS) - generated bindings will provide concrete implementations
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface Cryptec : NSObject
+
++ (NSString*)generate_mnemonic:(uint32_t)strength;
++ (NSString*)first_receive_address:(NSString*)mnemonic;
++ (NSString*)create_psbt:(NSString*)mnemonic to:(NSString*)to sats:(uint64_t)sats;
++ (NSString*)sign_psbt:(NSString*)mnemonic psbt:(NSString*)psbt_b64;
+
+@end
+
+NS_ASSUME_NONNULL_END

mobile/__tests__/nativeModuleIntegration.test.ts

@@ -0,0 +1,35 @@
+import { NativeModules } from 'react-native';
+import nativeBridge from '../src/nativeBridge';
+
+describe('native module integration (shim)', () => {
+  afterEach(() => {
+    jest.resetModules();
+  });
+
+  test('JS mock used when NativeModules not available', async () => {
+    const mn = await nativeBridge.generateMnemonic(128);
+    expect(typeof mn).toBe('string');
+    const addr = nativeBridge.firstReceiveAddressFromMnemonic(mn);
+    expect(typeof addr).toBe('string');
+  });
+
+  test('uses NativeModules when present (mocked)', async () => {
+    (NativeModules as any).Cryptec = {
+      generate_mnemonic: (s: number) => 'abandon abandon abandon ...',
+      first_receive_address: (m: string) => 'tb1qnative',
+      create_psbt: (m: string, t: string, s: number) => 'psbt-native',
+      sign_psbt: (m: string, p: string) => 'signed-native'
+    };
+
+    const m = await nativeBridge.generateMnemonic(128);
+    expect(m).toContain('abandon');
+    const addr = nativeBridge.firstReceiveAddressFromMnemonic('x');
+    expect(addr).toBe('tb1qnative');
+
+    const psbt = await nativeBridge.createPsbtMock('x', 'tb1qnative', 1000);
+    expect(psbt).toBe('psbt-native');
+
+    const signed = await nativeBridge.signPsbtMock('x', 'psbt-native');
+    expect(signed).toBe('signed-native');
+  });
+});

mobile/android/src/main/java/com/cryptec/CryptecModule.java

@@ -0,0 +1,39 @@
+package com.cryptec;
+
+import com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.bridge.ReactContextBaseJavaModule;
+import com.facebook.react.bridge.ReactMethod;
+import com.facebook.react.bridge.Promise;
+
+public class CryptecModule extends ReactContextBaseJavaModule {
+    public CryptecModule(ReactApplicationContext reactContext) {
+        super(reactContext);
+    }
+
+    @Override
+    public String getName() {
+        return "Cryptec";
+    }
+
+    @ReactMethod
+    public void generate_mnemonic(int strength, Promise p) {
+        // Native implementation should call into UniFFI-generated JNI bridge.
+        // Fallback: return an error so JS fallback can be used in dev/CI.
+        p.resolve("");
+    }
+
+    @ReactMethod
+    public void first_receive_address(String mnemonic, Promise p) {
+        p.resolve("");
+    }
+
+    @ReactMethod
+    public void create_psbt(String mnemonic, String to, double sats, Promise p) {
+        p.resolve("");
+    }
+
+    @ReactMethod
+    public void sign_psbt(String mnemonic, String psbt_b64, Promise p) {
+        p.resolve("");
+    }
+}

mobile/android/src/main/java/com/cryptec/CryptecPackage.java

@@ -0,0 +1,24 @@
+package com.cryptec;
+
+import com.facebook.react.ReactPackage;
+import com.facebook.react.bridge.NativeModule;
+import com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.uimanager.ViewManager;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+public class CryptecPackage implements ReactPackage {
+    @Override
+    public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
+        return Collections.emptyList();
+    }
+
+    @Override
+    public List<NativeModule> createNativeModules(ReactApplicationContext reactContext) {
+        List<NativeModule> modules = new ArrayList<>();
+        modules.add(new CryptecModule(reactContext));
+        return modules;
+    }
+}

mobile/ios/CryptecModule.m

@@ -0,0 +1,10 @@
+#import <React/RCTBridgeModule.h>
+
+@interface RCT_EXTERN_MODULE(Cryptec, NSObject)
+
+RCT_EXTERN_METHOD(generate_mnemonic:(NSInteger)strength resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject)
+RCT_EXTERN_METHOD(first_receive_address:(NSString*)mnemonic resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject)
+RCT_EXTERN_METHOD(create_psbt:(NSString*)mnemonic to:(NSString*)to sats:(nonnull NSNumber*)sats resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject)
+RCT_EXTERN_METHOD(sign_psbt:(NSString*)mnemonic psbt:(NSString*)psbt resolver:(RCTPromiseResolveBlock)resolve rejecter:(RCTPromiseRejectBlock)reject)
+
+@end