> For the complete documentation index, see [llms.txt](https://docs.coti.io/coti-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.coti.io/coti-documentation/coti-privacy-portal/developer-guide.md).

# Developer Guide

This guide is for developers who want to build, integrate, and interact with [`PrivateERC20`](https://github.com/coti-io/coti-contracts/blob/main/contracts/token/PrivateERC20/PrivateERC20.sol) tokens on COTI.

Whether you're:

* deploying a new private token
* integrating privacy into an existing smart contract
* writing tests
* connecting a frontend application

this guide walks you through the full development process.

## What you'll learn

By the end of this guide, you will be able to:

* understand what `PrivateERC20` is and how it differs from a standard ERC20
* create your own private token by extending the base contract
* mint and burn tokens using both public and encrypted amounts
* work with encrypted balances
* send encrypted transactions from a React app using ethers.js and the COTI SDK

## What this guide covers

This guide follows the full lifecycle of a `PrivateERC20` token:

* understanding the `PrivateERC20` model
* creating and deploying a private token
* minting and burning tokens
* reading encrypted balances
* sending encrypted transactions from a frontend


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