Are you looking Uniswap decentralized finance protocol

 Uniswap: Uniswap is a decentralized finance protocol that is used to exchange cryptocurrencies. Uniswap is also the name of the company that initially built the Uniswap protocol. The protocol facilitates automated transactions between cryptocurrency tokens on the Ethereum blockchain through the use of smart contracts. As of October 2020, Uniswap was estimated to be the largest decentralized exchange and the fourth-largest cryptocurrency exchange overall by daily trading volume.In March 2021, Uniswap was generating fees of approximately US$2–3 million daily for the liquidity providers who facilitate liquid markets for the cryptocurrencies being exchanged.

How Uniswap works : Uniswap runs on two smart contracts; an “Exchange” contract and a “Factory” contract. These are automatic computer programs that are designed to perform specific functions when certain conditions are met. In this instance, the factory smart contract is used to add new tokens to the platform and the exchange contract facilitates all token swaps, or “trades.” Any ERC20-based token can be swapped with another on the updated Uniswap v.2 platform.

Automated liquidity protocol : The way Uniswap solves the liquidity problem (described in the introduction) of centralized exchanges is through an automated liquidity protocol. This works by incentivizing people trading on the exchange to become liquidity providers (LPs): Uniswap users pool their money together to create a fund that’s used to execute all trades that take place on the platform. Each token listed has its own pool that users can contribute to, and the prices for each token are worked out using a math algorithm run by a computer (explained in “How token price is determined,” below). With this system, a buyer or seller does not have to wait for an opposite party to appear to complete a trade. Instead, they can execute any trade instantly at a known price provided there’s enough liquidity in the particular pool to facilitate it. 

In exchange for putting up their funds, each LP receives a token that represents the staked contribution to the pool. For example, if you contributed $10,000 to a liquidity pool that held $100,000 in total, you would receive a token for 10% of that pool. This token can be redeemed for a share of the trading fees. Uniswap charges users a flat 0.30% fee for every trade that takes place on the platform and automatically sends it to a liquidity reserve. Whenever a liquidity provider decides they want to exit, they receive a portion of the total fees from the reserve relative to their staked amount in that pool. The token they received which keeps a record of what stake they’re owed is then destroyed. After the Uniswap v.2 upgrade, a new protocol fee was introduced that can be turned on or off via a community vote and essentially sends 0.05% of every 0.30% trading fee to a Uniswap fund to finance future development. Currently, this fee option is turned off, however, if it is ever turned on it means LPs will start receiving 0.25% of pool trading fees.

How token price is determined : Another important element of this system is how it determines the price of each token. Instead of an order book system where the price of each asset is determined by the highest buyer and lowest seller, Uniswap uses an automated market maker system. This alternative method for adjusting the price of an asset based on its supply and demand uses a long-standing mathematical equation. It works by increasing and decreasing the price of a coin depending on the ratio of how many coins there are in the respective pool. It’s important to note that whenever someone adds a new ERC-20 token to Uniswap, that person has to add a certain amount of the chosen ERC-20 token and an equal amount of another ERC-20 token to start the liquidity pool. 

The equation for working out the price of each token is x*y=k, where the amount of token A is x and the amount of token B is y. K is a constant value, aka a number that doesn’t change. For example, Bob wants to trade chainlink (LINK) for ether using the Uniswap LINK/ETH pool. Bob adds a large number of LINK to the pool which increases the ratio of LINK in the pool to ether. Since the value K must remain the same, it means the cost of ether increases while the cost of link in the pool decreases. So the more LINK Bob puts in, the less ether he gets in return because the price of it increases.  The size of the liquidity pool also determines how much the price of tokens will change during a trade. The more money, aka liquidity, there is in a pool, the easier it is to make larger trades without causing the price to slide as much.

How to use Uniswap: Getting started with Uniswap is relatively straightforward, however, you will need to make sure you already have an ERC-20 supported wallet setup such as MetaMask, WalletConnect, Coinbase wallet, Portis, or Fortmatic.Once you have one of those wallets, you need to add ether to it in order to trade on Uniswap and pay for gas – this is what Ethereum transaction fees are called. Gas payments vary in price depending on how many people are using the network. Most ERC-20 compatible wallet services give you three choices when making a payment over the Ethereum blockchain: slow, medium or fast. Slow is the cheapest option, fast is the most expensive and medium is somewhere in between. This determines how quickly your transaction is processed by Ethereum network miners.

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