Goalz: Onchain Savings Accounts with a Purpose

Network Deployment Addresses

Arbitrum One

Contract	Address
USDC	0xaf88d065e77c8cC2239327C5EDb3A432268e5831
WETH	0x82aF49447D8a07e3bd95BD0d56f35241523fBab1
Goalz	0xD73EA7F07678B9f1C524C77cabc82fbEd4525EeA
Goalz USD Coin (glzUSDC)	0xAc800270c1FCEE96691DD7e5f851d2093f1481C8
Goalz Wrapped Ether (glzWETH)	0xC8C2CA42634bD0fE4FeE63196A57bf74c14117df

Base Mainnet

Contract	Address
USDC	0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
WETH	0x4200000000000000000000000000000000000006
Goalz	0x8afc985f3C23DdcA21B70Ecc65B3570d265AaeCf
Goalz USD Coin (glzUSDC)	0xbce33106991d18CAad8c655DB79617b7be424084
Goalz Wrapped Ether (glzWETH)	0x1fD2FC732e38B33bc282Ce248e948d6c3108f237

Base Sepolia Testnet

Contract	Address
Mock USDC	0xB731ac0a6783D18A41156c930361D3aB62e77606
Mock WETH	0xAa17431356ea6b50347dD740Bf6185A6129b7ed7
Goalz	0x5059dF9ab4D462D7Acc3d2057fbe56F009323591
Goalz USD Coin (glzUSDC)	0x27c8c8117fa4c0e0648e0e03173914bd0af9c094
Goalz Wrapped Ether (glzWETH)	0x0781d037c268ff1f78104425eee8aac42f58556a

Problem: Saving is hard

There are important things in life that we want to buy. Without savings, people either don't buy or will use credit to buy. Saving money in a single savings account can be challenging by itself. It becomes even harder when you are trying to save for multiple things at the same time within a single savings account. Tools like Mint support savings goals but are limited to one goal per one account. To make many savings goals with Mint requires making many seperate savings account. This can be done in traditional finance but it's difficult and out of reach for some people.

Existing Solutions & Their Limitations

Savings Goal Mobile Apps

These applications available in iOS and Android let you set up savings schedules. They will tell you how much you need to save to rach your goal and will give you alerts when it's time to save.

Limitations

• Not connected to a bank account
• Not automated so you have to manually make deposits
• Essentially a reminder tool

Mint Savings Goals

This application through mint let's you create goals for things like paying down debt or saving for a downpayment on a car/house. It includes features that take things like interest rates into account. You can select one of you connected accounts to use to track your progress

Limitations

• Must open a dedicated account for each goal
• Can't automated deposits through Mint, must be set up through your bank
• Goal tracking is view only

Goalz Solution: Blockchain-based Savings Accounts

Goalz is a decentralized application you can use to manage multiple savings goals in an user friendly way. Goalz uses Base blockchain to allow you to make individual savings accounts for all of your savings goals using a single wallet. Goalz makes it easy to make many savings goals and automate the savings process.

Features

• Create multiple savings goals
• Create automated deposits when creating a goal
• Select what asset you want to use to save in (e.g. USDC or ETH)

Why this solution solves the problem

The limitations of the traditional finance way of doing this are that you (1) need to open an account for each of your goals and (2) you must set up the automation on your own with your bank which might not support the automation.

The features of the Ethereum blockchain are put to full use with Goalz Savings app. Each goal can be it's own account with it's own asset to use for saving (e.g. ETH or USDC). Deposits can be automated using smart contracts like Gelato. There is no limitation on the number of accounts, no overhead to open an account, and the accounts themselves can be fully automated in ways that no traditional bank account can be.

Protocol Specification

Overview

• Users create one or more savings goal in the app by specifying:
  • What is the goal for?
  • Why are you saving for this goal?
  • How much is the goal amount?
  • When is the target date for the goal?
• After a user creates a goal, they can make deposits to the goal manually
• On deposit, funds are wrapped in a yield bearing token (i.e. Aave USD)
• Users can elect to automate the deposits by specifying:
  • How much to deposit?
  • How often should the deposit be made?

Usability

• This contract mints a non-transferable ERC20 token that represents the balance a user holds in Goalz
  • This token is used to track the balance a user has in portfolio and wallet apps
  • These tokens are glzTokens (glxUSDC, glxETH, etc.)
• This contract mints a non-transferable ERC721 token that represents each goal a user creates
  • This token is used to track the goals a user has in portfolio and wallet apps
  • These are Goalz (GOALZ)
• (Optionally) Goalz has a rewards token the Goalie (GOALIE)
  • Users earn Goalies for making deposits and reaching goals
  • Goalies can be redeemed for rewards

Goalz Contract

Inheritance

• @openzeppelin/contracts/token/ERC721/extensions/IERC721Enumerable.sol

Structs

• SavingsGoal
  • string what
  • string why
  • uint targetAmount
  • uint currentAmount
  • uint targetDate
• AutomatedDeposit
  • uint amount
  • uint frequency
  • uint lastDeposit

Variables

• ERC20 depositToken - the supported deposit token for the savings goal
• mapping(uint => SavingsGoal) savingsGoals - the mapping of savings goals to their ids
• mapping(uint => AutomatedDeposit) automatedDeposits - Maps savingsGoal ids to their automated deposits

Events

• GoalCreated(address saver, uint goalId, string what, string why, uint targetAmount, uint targetDate)
• DepositMade(address saver, uint goalId, uint amount)
• AutomatedDepositCreated(address saver, uint goalId, uint amount, uint frequency)
• AutomatedDepositCanceled(address saver, uint goalId)

Methods

• setGoal(string what, string why, uint targetAmount, uint targetDate)

  • Parameters
    • what is the name of the goal
    • why is the reason for the goal
    • targetAmount is the amount of the goal
    • targetDate is the date the goal should be reached
  • Pre-conditions
    • targetAmount is greater than 0
    • targetDate is greater than the current date
  • Post-conditions
    • A new SavingsGoal is created

• deposit(uint goalId, uint amount)

  • Parameters
    • goalId is the id of the goal to deposit to
    • amount is the amount to deposit into this goal
  • Pre-conditions
    • goalId is a valid goal id
    • amount is greater than 0
    • amount + currentAmount is less than or equal to targetAmount
    • Must approve this contract to spend amount of depositToken
  • Post-conditions
    • amount of depositToken is transferred from the sender to this contract
    • amount of depositToken is added to the currentAmount of the SavingsGoal

• withdraw(uint goalId)

  • Parameters
    • goalId is the id of the goal to withdraw from
  • Pre-conditions
    • goalId is a valid goal id
    • currentAmount is greater than 0
    • The msg.sender is the owner of this goalId
  • Post-conditions
    • currentAmount of depositToken is transferred from this contract to the sender

• automateDeposit(uint goalId, uint amount, uint frequency)

  • Parameters
    • goalId is the id of the goal to automate deposits for
    • amount is the amount to deposit into this goal
    • frequency is the frequency of deposits in seconds
  • Pre-conditions
    • goalId is a valid goal id
    • goalId does not already have an AutomatedDeposit
    • amount is greater than 0
    • frequency is greater than 0
    • Must approve this contract to spend amount of depositToken
  • Post-conditions
    • An AutomatedDeposit is created for the goalId

• cancelAutomateDeposit(uint goalId)

  • Parameters
    • goalId is the id of the goal to cancel automated deposits for
  • Pre-conditions
    • goalId is a valid goal id
    • goalId has an AutomatedDeposit
  • Post-conditions
    • The AutomatedDeposit for goalId is deleted

• automatedDeposit(uint goalId)

  • Parameters
    • goalId is the id of the goal to make an automated deposit for
  • Pre-conditions
    • goalId is a valid goal id
    • goalId has an AutomatedDeposit
    • now is greater than lastDeposit + automatedDeposit.frequency
  • Post-conditions
    • automatedDeposit.amount of depositToken is transferred from the goal's owner to this contract
    • automatedDeposit.amount of depositToken is added to the currentAmount of the SavingsGoal
    • automatedDeposit.lastDeposit is set to now