Uniflash Save

Description

Uniflash is a simple and decentralized protocol for flash loans, trying to follow the design of Uniswap. It supports both Eth and ERC20 tokens. All the fee goes to users.

Note that Uniflash is not audited yet, though there are enough test cases. It's currently deployed on the Ropsten network for testing.

For discussing and contributing to the next of Uniflash, please join this telegram group @Uniflash

Try out

One could use any smart contract interactor to play with Uniflash, e.g. https://justsmartcontracts.dev/. It's able to add a front-end similar to Uniswap later if the community likes the project.

Testing on Ropsten network:

1. Switch to Ropsten network
2. Load abi/uniflash-factory.json with address: 0x689bf4B0E69d113584830958c3A46f40F9B52093
3. Get the flash-loan address of Eth by calling getEthFlash with any interest factor from 1 to 10 (e.g. 9 means 0.09% fee rate)
4. Load abi/uniflash-eth.json with the address fetched in Step 3
5. Now one could use addLiquidity and removeLiquidity to deposit and withdraw your Eth
6. Feel free to play with the other functionalities

One can create a Pool for any ERC20 token using uniflash-factory, and then following similar steps to deposit and withdraw your ERC20 tokens in the flash loan pool.

Fee mechanism

For each token (including Eth), there are 10 pools initialized with fee rate ranging from 0.01%, 0.02%, to 0.10%. Users are free to choose a pool with a matched fee rate.

Why not a dynamic fee rate? The reasons are: 1. It's done on purpose to avoid using any price oracle to quantify the volume of each pool, so as to keep the protocol as simple as possible. 2. If the initial fee is high, then nobody would use it. The protocol would be stuck in the cold-start phase. However, with the current design, users are able to switch between pools with different fee rates. 3. Even though discrete fee rates are used, the pool sizes could change according to demands and supplies.

Authors

• Cheng Wang - polarker

Thank Uniswap for its pioneering work on DeFi design and implementation.