namillum/needing-organisation/newdocs/developer-portal/docs/dev/dev-txn-signing.mdx

Bubble Protocol SDK

---
id: dev-txn-signing
title: Signing
keywords:
  - signing
  - transitions
  - zilliqa
description: Zilliqa Transaction Signing
---

---

Before sending a transaction, one must first sign it with a **valid private key**. This can be done with one of the numerous SDKs provided by the Zilliqa team and community.

Signing is done against the Protobuf-serialised version of the transaction's contents. This is the reason why all SDKs depend on Protobuf to function. This step is **transparent** to you as a developer.

Example of providing a private key:

import Tabs from "@theme/Tabs";
import TabItem from "@theme/TabItem";

<Tabs
  defaultValue="js"
  values={[
    { label: 'JavaScript', value: 'js', },
    { label: 'Go', value: 'go', },
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<TabItem value="js">

```js
const { Zilliqa } = require("@zilliqa-js/zilliqa");
const { getAddressFromPrivateKey } = require("@zilliqa-js/crypto");
const zilliqa = new Zilliqa("https://dev-api.zilliqa.com");

const PRIVATE_KEY =
  "9afc1a1dab96127e902daaaec1a56c30346f007523c787c3bb62371c0e5a1be7";

zilliqa.wallet.addByPrivateKey(PRIVATE_KEY);
```

</TabItem>
<TabItem value="go">

```go
import (
	"github.com/Zilliqa/gozilliqa-sdk/account"
)

wallet := account.NewWallet()
wallet.AddByPrivateKey("e19d05c5452598e24caad4a0d85a49146f7be089515c905ae6a19e8a578a6930")
```

</TabItem>
<TabItem value="java">

```java
package com.firestack.example;

import com.firestack.laksaj.account.Wallet;

public class TransactionOperation {
    public static void main(String[] args) throws IOException, NoSuchAlgorithmException {
        Wallet wallet = new Wallet();
        String ptivateKey = "e19d05c5452598e24caad4a0d85a49146f7be089515c905ae6a19e8a578a6930";
        String address = wallet.addByPrivateKey(ptivateKey);
    }
}
```

</TabItem>
</Tabs>