# CCXT: Writing Trading Bots, The Easy Way! (Part I)

Introduction

CCXT is a powerful and versatile trading library that enables developers to connect to and interact with a vast number of cryptocurrency exchanges. It allows developers to write automated trading bots in Python, JavaScript, and other programming languages, making it an indispensable tool for any serious trader or investor.

In this article, we will provide an overview of the CCXT library, and guide you through the process of building a simple trading bot in Python. We will also provide links to external resources, including documentation, software, and libraries, to help you get started.

Overview of CCXT

CCXT is a unified, low-level library for interacting with cryptocurrency exchanges. It provides a common interface for accessing over 150 exchanges, including popular platforms like Binance, Coinbase Pro, Kraken, and Bitfinex.

CCXT Pro is a premium version of the original CCXT library, which is an open-source project maintained by a community of developers. The premium version includes additional features like faster performance, enhanced security, and direct support from the CCXT team.

CCXT Pro used to be available as a subscription-based service, with pricing plans starting at $29 per month. But now it is available freely and as part of CCXT library, may be utilized at no charge.

Getting Started with CCXT

To get started with CCXT, you will need to sign up for a subscription and obtain an API key from your chosen exchange. You can then install the CCXT library using pip, the Python package manager, by running the following command in your terminal:

pip install ccxt

Once you have installed the library, you can import it into your Python script using the following code:

import ccxt

You can then create an instance of the exchange you wish to trade on using the following code:

exchange = ccxt.binance({
    'apiKey': 'YOUR_API_KEY',
    'secret': 'YOUR_SECRET_KEY'
})

Replace YOUR_API_KEY and YOUR_SECRET_KEY with the corresponding values provided by your exchange.

Interacting with Exchanges using CCXT

CCXT provides a consistent interface for interacting with exchanges, regardless of the underlying API. This makes it easy to switch between exchanges, as the same code can be used for multiple platforms.

The basic operations that can be performed using CCXT include fetching market data, submitting orders, and managing positions.

Fetching Market Data

To fetch market data, you can use the fetch_ohlcv method, which retrieves the open, high, low, and close prices for a given trading pair and time frame. For example, to retrieve the 1-minute OHLCV data for BTC/USDT on Binance, you can use the following code:

ohlcv = await exchange.fetch_ohlcv('BTC/USDT', '1m')

Submitting Orders

To submit an order, you can use the create_order method, which allows you to specify the trading pair, order type, and order parameters. For example, to place a limit buy order for 0.1 BTC at a price of 50000 USDT/BTC on Binance, you can use the following code:

order = await exchange.create_order('BTC/USDT', 'limit', 'buy', 0.1, 50000)

Managing Positions

To manage positions, you can use the fetch_balance method, which retrieves your account balance and positions. For example, to retrieve your BTC balance on Binance, you can use the following code:

balance = await exchange.fetch_balance()
btc_balance = balance['BTC']['free']

Building a Simple Trading Bot using CCXT

Now that we have covered the basics of CCXT, let's build a simple trading bot that buys BTC whenever the price drops below a certain threshold.

We will start by defining the trading strategy, which in this case is based on a simple moving average crossover. The strategy involves calculating the 20-day moving average and the 50-day moving average of the BTC/USDT price, and placing a buy order whenever the 20-day moving average crosses above the 50-day moving average.

To implement this strategy, we will define a Python function called check_buy_signal that takes the current price and the historical price data as input, and returns a Boolean value indicating whether a buy signal is present. Here is the code for the check_buy_signal function:

def check_buy_signal(price, ohlcv):
    close_prices = [row[4] for row in ohlcv]
    ma20 = sum(close_prices[-20:]) / 20
    ma50 = sum(close_prices[-50:]) / 50
    return ma20 > ma50 and price < ma20

Next, we will define the main trading loop, which retrieves the current price and historical price data from the exchange, and checks for a buy signal using the check_buy_signal function. If a buy signal is present, the bot places a market buy order for 0.01 BTC.

Here is the complete code for the trading bot:

import ccxt

def check_buy_signal(price, ohlcv):
    close_prices = [row[4] for row in ohlcv]
    ma20 = sum(close_prices[-20:]) / 20
    ma50 = sum(close_prices[-50:]) / 50
    return ma20 > ma50 and price < ma20

async def main():
    exchange = ccxt.binance({
        'apiKey': 'YOUR_API_KEY',
        'secret': 'YOUR_SECRET_KEY'
    })
    symbol = 'BTC/USDT'
    while True:
        try:
            ticker = await exchange.fetch_ticker(symbol)
            ohlcv = await exchange.fetch_ohlcv(symbol, '1d')
            price = ticker['last']
            if check_buy_signal(price, ohlcv):
                order = await exchange.create_order(symbol, 'market', 'buy', 0.01)
                print(f"Placed buy order for {symbol}: {order['id']}")
            else:
                print(f"No buy signal for {symbol} at price {price}")
            await ccxt.asyncio.sleep(60)
        except Exception as e:
            print(e)

if __name__ == '__main__':
    ccxt.asyncio.run(main())

Replace YOUR_API_KEY and YOUR_SECRET_KEY with your Binance API credentials, and adjust the order size and time frame as desired.

Conclusion

CCXT is a powerful tool for building automated trading bots in Python and other programming languages. With its unified interface and support for over 150 exchanges, it simplifies the process of interacting with cryptocurrency markets and enables developers to focus on building profitable trading strategies.

In this article, we provided an overview of CCXT and demonstrated how to build a simple trading bot using the library. We hope that this article has been useful and that it inspires you to explore the world of automated trading further.

External Resources

CCXT documentation: https://docs.ccxt.com/
CCXT GitHub repository: https://github.com/ccxt/ccxt
Python documentation: https://docs.python.org/3/
Binance API documentation: https://binance-docs.github.io/apidocs/spot/en/