Uniswap Smart Path

Project Information

Code Quality

Overview

With several V2 and V3 pools, and 2 or 3 tokens per path, there may be quite a few routes to perform a swap. And if you add the gas fees into the equation, it is not straightforward to be sure to get the best deal.

The object of this library is to find the path(s), from v2 and v3 pools, to swap with the best price, including gas fees, and to return it/them in order to be used directly with the UR codec, along with a percentage to know how to divide the amount between them.

⚠ This project is a work in progress. Not all features have been implemented yet. For instance the gas fees is not evaluated in the current version.

⚠ This tool does not replace your own due diligence to find the best price/path to swap any token.

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Installation

A good practice is to use Python virtual environments, here is a tutorial.

The library can be pip installed from pypi.org as usual:

# update pip to latest version if needed
pip install -U pip

# install the decoder from pypi.org
pip install uniswap-smart-path

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Usage

The library exposes a class, SmartPath with a public method get_swap_in_path() that can be used to find the best path/price. For performance's sake, it is asynchronous. Currently, it supports only the Ethereum blockchain.

from uniswap_smart_path import SmartPath

smart_path = await SmartPath.create(async_w3)  # where async_w3 is your AsyncWeb3 instance
path = await smart_path.get_swap_in_path(amount_in_wei, token0_address, token1_address)

You can also create the SmartPath instance from a rpc endpoint:

from uniswap_smart_path import SmartPath

smart_path = await SmartPath.create(rpc_endpoint=rpc_endpoint)

V2 or V3 pools only

The factory method SmartPath.create_v2_only() can be used to create a SmartPath instance that will look for the best path in V2 pools only. Currently, it supports only the Ethereum blockchain.

from uniswap_smart_path import SmartPath

smart_path = await SmartPath.create_v2_only(rpc_endpoint=rpc_endpoint)  # could also use an AsyncWeb3 instance i/o rpc

Same thing if you wish to look into V3 pools only, just use SmartPath.create_v3_only() Currently, it supports only the Ethereum blockchain.

from uniswap_smart_path import SmartPath

smart_path = await SmartPath.create_v3_only(rpc_endpoint=rpc_endpoint)  # could also use an AsyncWeb3 instance i/o rpc

Custom pools and blockchains

A custom SmartPath can be created with the factory method SmartPath.create_custom()

from uniswap_smart_path import SmartPath

pivot_tokens = (wbnb_address, usdt_address, usdc_address, dai_address)  # BSC addresses
v3_pool_fees = (100, 500, 2500, 10000)  # Pancakeswap v3 fees

smart_path = await SmartPath.create_custom(
        w3,  # BSC AsyncWeb3 instance
        pivot_tokens=pivot_tokens,
        v3_pool_fees=v3_pool_fees,
        v2_router=pancakeswapv2_address,
        v2_factory=pancakeswapv2_factory,
        v3_quoter=pancakeswapv3_quoter_address,
        v3_factory=pancakeswapv3_factory,
    )

Result

Examples of output paths that you can use with the UR codec to encode a transaction.

Single path

(
    {
        'path': ('0xD533a949740bb3306d119CC777fa900bA034cd52', 3000, '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2', 3000, '0x9f8F72aA9304c8B593d555F12eF6589cC3A579A2'),
        'function': 'V3_SWAP_EXACT_IN',
        'weight': 100,
        'estimate': 128331138758276360764
    },
)

Multi path

Here, 90% of the amount should be swapped on a V3 pool and 10% on a V2 pool, all that in a single transaction using the UR codec.

(
    {
        'path': ('0x1f9840a85d5aF5bf1D1762F925BDADdC4201F984', '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2'),
        'function': 'V2_SWAP_EXACT_IN',
        'weight': 10,
        'estimate': 32858922292711987411
     },
    {
        'path': ('0x1f9840a85d5aF5bf1D1762F925BDADdC4201F984', 3000, '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2'),
        'function': 'V3_SWAP_EXACT_IN',
        'weight': 90,
        'estimate': 295000857928717844546
    }
)