An Introduction to Beanstalk

A Decentralized Credit Based Stablecoin Protocol

Beanstalk is a decentralized credit based algorithmic stablecoin protocol that is built on Ethereum. Beanstalk uses credit instead of collateral to create price stability relative to a non-blockchain-native asset. Beanstalk does not have any collateral requirements. The first Beanstalk issues a USD stablecoin (USDBean Logo) on the Ethereum blockchain.

Background

Stablecoins are cryptocurrencies that attempt to peg their market value to some external reference (e.g., USD). Current stablecoin implementations have two key problems: centralization and collateral requirements.

The practicality of using Decentralized Finance is limited by the lack of a decentralized, collateral-free stablecoin. Borrowing rates on USD stablecoins remain excessively high, even as their supply increases rapidly. Supply cannot meet demand due to collateral requirements.

A New Type of Stablecoin

Beanstalk uses credit instead of collateral to create a decentralized, liquid, blockchain-native asset, which is stable relative to the value of a non-blockchain-native asset.

Beanstalk issues 3 ERC-20 Standard tokens: (1) Beans, the Beanstalk stablecoin, (2) Stalk, a yield generating governance token, and (3) Seeds, which yield 1/10000 Stalk every Season. Seasons are the Beanstalk-native timekeeping mechanism. Each Season is ∼1 hour long.

Beanstalk creates protocol-native financial incentives to encourage participation in peg maintenance and governance without affecting Bean users.

How Does Beanstalk Work?

Beanstalk relies on 3 interconnected parts: (1) a decentralized price oracle, (2) a decentralized governance mechanism: the Silo, and (3) a decentralized credit facility: the Field.

1. Decentralized Price Oracle

Beanstalk uses 2 Uniswap liquidity pools – USDC:ETH and USDBean Logo:ETH – to create a decentralized price oracle. When the ratios of the two pools are identical, the price of Bean Logo1 is considered equal to $1. By trading against ETH instead of USDC directly, Beanstalk minimizes exposure to the centralized operators of USDC.

Beanstalk calculates a time weighted average price for Bean Logo1 over each Season.

2. Decentralized Governance Mechanism: The Silo

Beanstalk uses the Silo, the Beanstalk Decentralized Autonomous Organization, to create a robust decentralized governance mechanism. Any Bean owner can earn yield from passive participation in Beanstalk governance by Depositing their assets in the Silo to receive Seeds and Stalk. Stalk owners can submit and vote on Beanstalk Improvement Proposals and collect a portion of Bean supply increases as interest.

A large value of Deposits and diverse community of Stalk owners creates a robust decentralized governance mechanism. To encourage consistent security: (1) Seeds yield Stalk every Season; (2) the associated amount of Seeds and Stalk from a given Deposit must be forfeited when the Deposit is Withdrawn from the Silo, and (3) Deposits can be Withdrawn from the Silo at any time but are Frozen for 24 full Seasons after Withdrawal.

Deep and consistent liquidity in the Bean:ETH Uniswap liquidity pool improves stability. LP providers to the USDBean Logo:ETH Uniswap liquidity pool can also Deposit their LP tokens in the Silo to earn Seeds and Stalk. LP token Deposits receive twice as many Seeds per Bean Deposited as Bean Deposits.

3. Decentralized Credit Facility: The Field

Beanstalk relies on a decentralized community of lenders to maintain Bean price stability. The faster Beanstalk can attract creditors, the more stable the Bean price. Bean lending takes place in the Field.

Soil is the pre-approved number of Beans that can be lent to Beanstalk. Any time Beanstalk is willing to issue debt, there is Soil in the Field. Any Beans not in the Silo can be lent to Beanstalk in exchange for Pods.

Pods are the Beanstalk-native debt asset. Bean loans have a fixed interest rate and unknown maturity date. The number of Pods that grow from 1 Sown Bean is determined by the Weather – the Beanstalk-native interest rate – at the time of Sowing. Pods ripen and become Harvestable (redeemable) for Bean Logo1 on a First In, First Out basis during future Bean supply increases.

How Does Beanstalk Create Stability?

Beanstalk creates stability during both long run decreases and increases in demand for Beans. At the beginning of each Season, Beanstalk evaluates the Beanstalk oracle price and the Beanstalk debt level and dynamically adjusts the Bean supply, Soil supply and Weather. When the Bean price is too low, Beanstalk increase the Soil supply and raises the Weather.

When the Bean price is too high, Beanstalk increases the Bean supply and lowers the Weather. Half of Bean supply increases go to Pod Harvests. The other half are distributed to Stalk owners and Deposited in the Silo. If the Bean price is too high and the debt level is excessively low for 24 consecutive Seasons, Beanstalk sells Beans directly on Uniswap to return the Bean price to $1.

A reasonable debt level and consistent credit history attract creditors. When the Beanstalk debt level is excessively high or low, the Weather changes more aggressively to return Beanstalk to a more reasonable level of debt. Beanstalk is willing to issue debt every Season.

How can I participate in Beanstalk?

Visit the Beanstalk website at app.bean.money.

Visit the “How To Beanstalk” document on the website for step by step instructions on participation.