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apps/docs/05-developer-guides/01-fluter-sdk.md

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+# Flutter SDK
+
+With the Flutter SDK, you can add functionality to buttons in your app to interact with a vault contract. You only need **three lines of code** to set up a vault and perform actions like deposits! Here’s how to use it:
+
+1. **Obtain the Vault Contract Address:** You need the contract address for the vault where you want users to deposit. This can be got from the Dapp
+
+2. **Create a Vault Instance:** Set up an instance of the vault in your code.
+
+3. **Use Vault Functions:** Call `vault.deposit`, `vault.balance`, or `vault.withdraw` as needed.
+
+## Example Code
+
+Below is an example showing how to create a vault instance and call the `deposit` function:
+
+```dart
+import 'package:defindex_sdk/defindex_sdk.dart';
+
+// Create a vault instance
+var vault = Vault(
+  sorobanRPCUrl: 'https://soroban-testnet.stellar.org',
+  network: SorobanNetwork.TESTNET,
+  contractId: 'CD76H2IVRMRMLE4KZXLAVK3L3CO7PENUB3X4VB2FQVUAFVAJMQYQIFDE',
+);
+
+// Make a deposit
+String? transactionHash = await vault.deposit(
+  'GCW36WQUHJASZVNFIIL7VZQWL6Q72XT6TAU6N3XMFGTLSNE2L7LMJNWT', // User's Stellar address
+  100.0, // Amount to deposit
+  (transaction) async => signerFunction(transaction),
+);
+
+print('Transaction hash: $transactionHash');
+
+// Optionally, show a dialog or snackbar with the result
+ScaffoldMessenger.of(context).showSnackBar(
+  SnackBar(content: Text('Transaction hash: $transactionHash')),
+);