evm-defi - Dokrypt

Overview

The most comprehensive template. Includes a Uniswap-style AMM (Factory, Pair, Router), a collateralized lending vault, Synthetix-style staking rewards, and a price oracle. Comes with IPFS, a subgraph indexer, Blockscout explorer, and Chainlink mock oracle as services.


Difficulty	Advanced
Category	DeFi
Chains	Ethereum
Services	IPFS, Subgraph, Blockscout, Chainlink Mock
License	Apache-2.0

Quick Start

dokrypt init my-defi --template evm-defi
cd my-defi
dokrypt up
# ethereum    Ready  http://localhost:8545
# ipfs        Ready  http://localhost:5001
# blockscout  Ready  http://localhost:4000
# oracle      Ready  chainlink-mock

Generated Files

my-defi

dokrypt.yaml

foundry.toml

README.md

contracts

token

DeFiToken.sol

amm

Factory.sol

Pair.sol

Router.sol

lending

LendingVault.sol

InterestModel.sol

staking

StakingRewards.sol

oracle

PriceOracle.sol

test

amm

Factory.t.sol

Router.t.sol

lending

LendingVault.t.sol

staking

StakingRewards.t.sol

scripts

deploy-amm.js

deploy-lending.js

deploy-staking.js

Contracts

DeFiToken.sol

ERC-20 with governance delegation, minting, and burning. Constructor:

constructor(string memory name, string memory symbol, uint256 initialSupply)

Function	Access	Description
Standard ERC-20	Public	`transfer`, `approve`, `transferFrom`
`mint(to, amount)`	Owner	Mint new tokens
`burn(amount)`	Public	Burn your tokens
`delegate(delegatee)`	Public	Delegate voting power

AMM Module

A Uniswap V2-style automated market maker with three contracts.

Factory.sol

Creates and tracks liquidity pairs using CREATE2 for deterministic addresses.

Function	Access	Description
`createPair(tokenA, tokenB)`	Public	Deploy a new pair contract
`computePairAddress(tokenA, tokenB)`	View	Predict pair address before creation
`allPairsLength()`	View	Total number of pairs
`setFeeTo(newFeeTo)`	Owner	Set fee recipient

Uses CREATE2 with salt keccak256(abi.encodePacked(token0, token1)).

Pair.sol

Liquidity pool implementing the x * y = k constant product invariant. Key Constants:

MINIMUM_LIQUIDITY = 1000 — Permanently locked on first mint
SWAP_FEE = 3 — 0.3% swap fee (3/1000)

Function	Access	Description
`initialize(token0, token1)`	Factory	One-time pair setup
`mint(to)`	Public	Add liquidity, receive LP tokens
`burn(to)`	Public	Remove liquidity, burn LP tokens
`swap(amountOut0, amountOut1, to)`	Public	Swap tokens (constant product enforced)
`skim(to)`	Public	Withdraw excess tokens
`sync()`	Public	Sync reserves to actual balances

Features:

ERC-20 LP tokens for liquidity providers
TWAP (Time-Weighted Average Price) oracle via price0CumulativeLast and price1CumulativeLast
Flash swap support

Events: Mint, Burn, Swap, Sync

Router.sol

High-level interface with deadline protection and slippage guards.

Function	Access	Description
`addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin, to, deadline)`	Public	Provide liquidity with slippage protection
`removeLiquidity(tokenA, tokenB, liquidity, amountAMin, amountBMin, to, deadline)`	Public	Remove liquidity
`swapExactTokensForTokens(amountIn, amountOutMin, path[], to, deadline)`	Public	Swap with exact input
`swapTokensForExactTokens(amountOut, amountInMax, path[], to, deadline)`	Public	Swap with exact output

All functions have deadline parameter — reverts if block.timestamp > deadline. Events: LiquidityAdded, LiquidityRemoved, SwapExecuted

LendingVault.sol

Collateralized lending with liquidation mechanics. Constants:

Constant	Value	Description
`COLLATERAL_FACTOR`	75% (7500 bp)	Max borrow relative to collateral
`LIQUIDATION_THRESHOLD`	80% (8000 bp)	Position becomes liquidatable
`LIQUIDATION_BONUS`	105% (10500 bp)	5% bonus for liquidators

Functions:

Function	Access	Description
`depositCollateral(token, amount)`	Public	Deposit collateral
`withdrawCollateral(token, amount)`	Public	Withdraw collateral (health check)
`borrow(amount)`	Public	Borrow against collateral
`repay(amount)`	Public	Repay debt
`liquidate(borrower, collateralToken, debtRepaid)`	Public	Liquidate unhealthy position
`addCollateral(token)`	Owner	Add supported collateral type
`accrueInterest()`	Public	Update interest accrual
`getUserHealthFactor(user)`	View	Check position health
`isLiquidationEligible(user)`	View	Check if liquidatable
`getMaxBorrowable(user)`	View	Max borrow amount

Liquidation Flow:

Borrower’s health factor drops below threshold (collateral value / debt > 80%)
Liquidator calls liquidate() with the debt amount to repay
Liquidator receives collateral worth 105% of repaid debt (5% bonus)
Borrower’s debt and collateral are reduced accordingly

Events: CollateralDeposited, CollateralWithdrawn, Borrowed, Repaid, Liquidated, InterestAccrued

InterestModel.sol

Kinked linear interest rate model. Rates increase slowly at low utilization and steeply at high utilization.

Function	Access	Description
`calculateInterestRate(totalBorrowed, totalAvailable)`	View	Returns annual interest rate

StakingRewards.sol

Same Synthetix-style staking as the evm-token template. See evm-token StakeRewards for full details.

PriceOracle.sol

Simple owner-managed price feed for the lending vault.

Function	Access	Description
`setPrice(token, price)`	Owner	Set token price
`setPrices(tokens[], prices[])`	Owner	Batch update prices
`getPrice(token)`	View	Get current price
`isPriceStale(token)`	View	Check if price is > 1 hour old

Deployment

Deploy AMM

npx hardhat run scripts/deploy-amm.js --network localhost

Deploys Factory, Router, test tokens, creates a pair, and adds initial liquidity.

Deploy Lending

npx hardhat run scripts/deploy-lending.js --network localhost

Deploys borrow token (USDT), collateral token (WETH), InterestModel, PriceOracle, and LendingVault. Configures prices, adds collateral support, and supplies initial tokens.

Deploy Staking

npx hardhat run scripts/deploy-staking.js --network localhost

Deploys staking and reward tokens, StakingRewards contract, transfers reward funds, sets duration, and notifies the contract.

Testing Workflows

AMM Testing

# Start environment
dokrypt up

# Deploy AMM
npx hardhat run scripts/deploy-amm.js --network localhost

# Test swaps, liquidity operations
dokrypt test run --filter "amm"

Lending Testing with Price Manipulation

# Deploy lending vault
npx hardhat run scripts/deploy-lending.js --network localhost

# Deposit collateral and borrow
# Then manipulate oracle price to test liquidations

# Run lending tests
dokrypt test run --filter "lending"

Staking with Time Travel

# Deploy staking
npx hardhat run scripts/deploy-staking.js --network localhost

# Stake tokens, then fast-forward time
dokrypt chain time-travel 30d

# Check accumulated rewards
dokrypt test run --filter "staking"

​Overview

​Quick Start

​Generated Files

​Contracts

​DeFiToken.sol

​AMM Module

​Factory.sol

​Pair.sol

​Router.sol

​LendingVault.sol

​InterestModel.sol

​StakingRewards.sol

​PriceOracle.sol

​Deployment

​Deploy AMM

​Deploy Lending

​Deploy Staking

​Testing Workflows

​AMM Testing

​Lending Testing with Price Manipulation

​Staking with Time Travel

Overview

Quick Start

Generated Files

Contracts

DeFiToken.sol

AMM Module

Factory.sol

Pair.sol

Router.sol

LendingVault.sol

InterestModel.sol

StakingRewards.sol

PriceOracle.sol

Deployment

Deploy AMM

Deploy Lending

Deploy Staking

Testing Workflows

AMM Testing

Lending Testing with Price Manipulation

Staking with Time Travel