CowSwap is the first trading interface built on top of Gnosis Protocol v2.

It allows you to buy and sell tokens using gas-less orders that are settled peer-to-peer among its users or into any on-chain liquidity source while providing MEV protection.

• 🐮Official Website🐮: https://cowswap.exchange/

  • ENS Website (alternative): https://cowswap.eth.link, or https://cowswap.eth/ if you have MetaMask or an ENS compatible browser.
  • The website can also be run locally, or from IPFS. Every release will have an IPFS hash associated, available in the Releases section.

• Docs: https://docs.cowswap.exchange

• Stats: https://dune.xyz/gnosis.protocol/Gnosis-Protocol-V2

• Twitter: @gnosisPM

• Reddit: /r/gnosisPM

• Discord: https://chat.cowswap.exchange

Please see the:

• Gnosis Protocol: Smart contracts
• Gnosis Protocol: Services

You can block an entire list of tokens by passing in a tokenlist like here or you can block specific tokens by adding them to unsupported.tokenlist.json.

Install Dependencies

yarn

Run

yarn start

Unit testing

yarn test

Integration test

Normally:

yarn build
yarn integration-test

If we want to use the Cypress UI:

yarn build
yarn serve
yarn cypress

If we want to use the Cypress UI, and live reloading on the web app:

yarn start:default
yarn cypress

Configuring the environment (optional)

The app has some default configuration, but it's highly encouraged to define your own.

Local configuration

Make a copy of .env named .env.local, this will allow you to set your own configuration only in your local environment.

Production configuration

Modify the environment variables in .env.production, or override them in build time.

Price feeds

CowSwap tries to find the best price available onchain using some price feeds.

All price feeds are enabled by default, but they can be individually disabled by using an environment variable:

Name	Environment variable	Type	Description
Gnosis Protocol	REACT_APP_PRICE_FEED_GP_ENABLED	boolean (default = true)	Gnosis Protocol price estimation. Used for all price estimation.
Paraswap	REACT_APP_PRICE_FEED_PARASWAP_ENABLED	boolean (default = true)	Paraswap price estimation. Used for all price estimations.
0x	REACT_APP_PRICE_FEED_0X_ENABLED	boolean (default = true)	0x price estimation. Used for all price estimation.
Coingecko	REACT_APP_PRICE_FEED_COINGECKO_ENABLED	boolean (default = true)	Coingecko price estimation. Used only for USD estimations to calculate the slippage on the trade.

Metadata attached to orders (AppData)

The app will attach some metadata to all orders.

This metadata will be sent to the smart contract as an hexadecimal value in an order field called AppData. This value comes from hashing the content of a metadata JSON containing some information about the trade.

Any web app or client using Gnosis Protocol can upload to IPFS a metadata JSON and use the digest hex to attach that information to the order.

For example, CowSwap uploaded the file https://cloudflare-ipfs.com/ipfs/QmTDarZ47oek1miuRd8uuNCy5AFfjzQbWJ7348izx9N8wQ which has the hexadecimal digest 0x487B02C558D729ABAF3ECF17881A4181E5BC2446429A0995142297E897B6EB37 (See CID Explorer for more details).

The format of the JSON follows this typescript format: <src/custom/utils/metadata.ts>

To set your own AppData, change REACT_APP_DOMAIN_REGEX_<environment> environment variable. Ask for yours at chat.cowswap.exchange/. For more details, check out the environment file (<.env>)

Supported networks

You can change the supported networks and their RPC endpoint.

To have the interface default to a different network when a wallet is not connected:

1. Change REACT_APP_NETWORK_ID to "{YOUR_NETWORK_ID}". This will be your default network id
2. Define your own list of supported networks:

REACT_APP_SUPPORTED_CHAIN_IDS="1,4,100"
REACT_APP_NETWORK_URL_1=https://mainnet.infura.io/v3/{YOUR_INFURA_KEY}
REACT_APP_NETWORK_URL_4=https://rinkeby.infura.io/v3/{YOUR_INFURA_KEY}
REACT_APP_NETWORK_URL_100=https://rpc.xdaichain.com

API endpoints

Fee quote requests and posting orders are sent to an API. This API has the responsibility of collecting orders and handing them to the solvers.

The reference implementation of th API is gp-v2-services.

The API endpoint is configured using the environment variable {XDAI|RINKEBY|MAINNET} to e.g. "http://localhost:8080/api" when running the services locally.

Wallet Connect bridge

Wallet Connect allows to connect the app to any Wallet Connect supported wallet.

In order to do so, it uses a Websocket, that can be configured using: the env var WALLET_CONNECT_BRIDGE.

Sitemap

The sitemap can be found in <./public/sitemap.xml>

To update its content:

1. Edit the list of pages in <./src/custom/sitemap.js>
2. Run yarn sitemap
3. Commit the changes to git