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DeFiPy

Uniswap V2 API

Protocol-specific classes for Uniswap V2 — the constant-product (x · y = k) AMM. These live in uniswappy and are imported into DeFiPy’s namespace at install time.

When working through DeFiPy’s Core API, you typically don’t touch these classes directly — Join, Swap, AddLiquidity, etc., dispatch to them under the hood. You’ll reach for them when you need to construct a pool from scratch (the factory.deploy(exchg_data) pattern), inspect protocol-specific state, or extend the library.

Public classes

Section titled “Public classes”

Factory and exchange

Section titled “Factory and exchange”
ClassModulePurpose
UniswapFactoryuniswappy.cpt.factoryDeploys new pools. The Join operation runs against pool instances returned by factory.deploy(exchg_data).
UniswapExchangeuniswappy.cpt.exchgThe pool itself — holds reserves, fee accumulators, LP-token supply, and the per-user LP-balance ledger.
UniswapExchangeDatauniswappy.cpt.exchgConfiguration object passed to the factory: token pair, symbol, address.

Tokens

Section titled “Tokens”
ClassModulePurpose
ERC20uniswappy.ercTest token type used throughout DeFiPy. Constructor takes a name and address; instances are passed by reference to swap/deposit ops.
LPERC20uniswappy.ercLP-token type. Returned by factory.deploy; can itself be used as a base token in a layered pool.

Math and tools

Section titled “Math and tools”
ModulePurpose
uniswappy.cpt.indexRebaseIndexToken, SettlementLPToken — the inverse-token primitives DeFiPy uses for paper-vs-settlement value conversion.
uniswappy.cpt.quoteLPQuote, IndexTokenQuote — fee-aware and fee-free quoting. The DeFiPy LPQuote page documents the full surface.
uniswappy.analytics.riskUniswapImpLoss — V2 IL math used by AnalyzePosition and SimulatePriceMove.

Construction example

Section titled “Construction example”
from defipy import *


tkn = ERC20("TKN", "0x111")
eth = ERC20("ETH", "0x09")
exchg_data = UniswapExchangeData(tkn0 = eth, tkn1 = tkn, symbol = "LP", address = "0x011")


factory = UniswapFactory("ETH pool factory", "0x2")
lp = factory.deploy(exchg_data)
# lp is a UniswapExchange instance, ready for Join().apply(...)

Notes

Section titled “Notes”
  • The fee is hard-coded at 30 bps. UniswapExchange has no .fee attribute — the multiplier 997/1000 is baked into get_amount_out0/1. This is correct for canonical V2; non-30-bps V2 forks would need a different exchange class.
  • First-mint sentinel. V2’s MINIMUM_LIQUIDITY is burned to address "0" on first Join. Filter out the "0" entry when iterating LP holders.
  • token0 / token1 are bare strings. Not full ERC20 objects. The full ERC20 instance lives at factory.token_from_exchange[lp.name][lp.token0].

See also

Section titled “See also”