Abstract Interface

• 📘 Join: joins X and Y amounts to pool

• 📘 Swap: swaps X for Y (and vice verse) via out-given-in or in-given-out

• 📘 AddLiquidity: adds liquidity using token or share amounts

• 📘 RemoveLiquidity: removes liquidity using token or share amounts

To download notebook to this tutorial, see here

from defipy import *

user_nm = 'user_test'

amt_dai = 10000000
denorm_wt_dai = 10

amt_eth = 67738.6361731024
denorm_wt_eth = 40

init_pool_shares = 100

dai = ERC20("DAI", "0x111")
dai.deposit(None, amt_dai)

weth = ERC20("WETH", "0x09")
weth.deposit(None, amt_eth)

bgrp = BalancerVault()
bgrp.add_token(dai, denorm_wt_dai)
bgrp.add_token(weth, denorm_wt_eth)

📘 Join

• Class: 📘 defipy.process.Join

  • Purpose: Simplifies initial liquidity addition to Balancer pools.

  • Methods:

    • apply(pool, user: str, amount_shares: float)

      • Parameters:

        • pool: Pool instance (e.g., created via Primitive Interface).

        • user: User address.

        • amount_shares: Amount of initial pool shares.

    • Output: Liquidity added to the pool.

bfactory = BalancerFactory("WETH pool factory", "0x2")
exchg_data = BalancerExchangeData(vault = bgrp, symbol="LP", address="0x011")
lp = bfactory.deploy(exchg_data)

Join().apply(lp, user_nm, init_pool_shares)
lp.summary()

Balancer Exchange: DAI-WETH (LP)
Reserves: DAI = 10000000, WETH = 67738.6361731024
Weights: DAI = 0.2, WETH = 0.8
Pool Shares: 100

📘 Swap (out-given-in)

• Class: 📘 defipy.process.Swap

  • Purpose: Facilitates token swaps on Balancer pools.

  • Methods:

    • apply(pool, token_in: ERC20, token_out: ERC20, user: str, amount_tkn_in: float)

      • Parameters:

        • pool: Pool instance to perform the swap on.

        • token_in: ERC20 token to swap in.

        • token_out: ERC20 token to swap out.

        • user: User address (string) executing the swap.

        • amount_tkn_in: Amount of token_in to swap.

    • Output: Executes the swap from token_in to token_out for the user

amt_tkn_in = 10000
tkn_in = dai
tkn_out = weth

res = Swap(Proc.SWAPOUT).apply(lp, tkn_in, tkn_out, user_nm, amt_tkn_in)
lp.summary()

print(f"{amt_tkn_in} {tkn_in.token_name} was swapped into {res['tkn_out_amt']} {tkn_out.token_name}")

Balancer Exchange: DAI-WETH (LP)
Reserves: DAI = 10010000, WETH = 67721.75437414162
Weights: DAI = 0.2, WETH = 0.8
Pool Shares: 100

10000 DAI was swapped into 16.881798960778035 WETH

📘 Swap (in-given-out)

• Class: 📘 defipy.process.Swap

  • Purpose: Facilitates token swaps on Balancer pools.

  • Methods:

    • apply(pool, token_in: ERC20, token_out: ERC20, user: str, amount_tkn_in: float)

      • Parameters:

        • pool: Pool instance to perform the swap on.

        • token_in: ERC20 token to swap in.

        • token_out: ERC20 token to swap out.

        • user: User address (string) executing the swap.

        • amount_tkn_out: Amount of token_out to swap.

    • Output: Executes the swap from token_out to token_in for the user

amt_tkn_out = 20
tkn_out = weth
tkn_in = dai

res = Swap(Proc.SWAPIN).apply(lp, tkn_in, tkn_out, user_nm, amt_tkn_out)
lp.summary()

print(f"{amt_tkn_out} {tkn_out.token_name} was swapped into {res['tkn_in_amt']} {tkn_in.token_name}")

Balancer Exchange: DAI-WETH (LP)
Reserves: DAI = 9998136.750149786, WETH = 67741.75437414162
Weights: DAI = 0.2, WETH = 0.8
Pool Shares: 100

20 WETH was swapped into 11863.249850213939 DAI

📘 AddLiquidity (based on token amounts)

• Class: 📘 defipy.process.AddLiquidity

  • Purpose: Adds liquidity to existing Balancer pools, handling token amounts and liquidity tokens minting.

  • Methods:

    • apply(pool, token_in: ERC20, user: str, amount_in: float)

      • Parameters:

        • pool: Pool instance to perform the swap on.

        • token_in: ERC20 token to swap from.

        • user: User address (string) providing liquidity.

        • amount_in: Amount of token_in to swap.

    • Output: Adds the specified token amounts to the pool and mints liquidity tokens to the user.

tkn_in = weth
amt_tkn_in = 25

res = AddLiquidity(Proc.ADDTKN).apply(lp, tkn_in, user_nm, amt_tkn_in)
lp.summary()

print(f"{amt_tkn_in} {tkn_in.token_name} was added resulting in anadditional {res['shares_in_amt']} LP shares")

Balancer Exchange: DAI-WETH (LP)
Reserves: DAI = 9998136.750149786, WETH = 67766.75437414162
Weights: DAI = 0.2, WETH = 0.8
Pool Shares: 100.0295080381873

25 WETH was added resulting in anadditional 0.029508038187306896 LP shares

📘 AddLiquidity (based on LP share amounts)

• Class: 📘 defipy.process.AddLiquidity

  • Purpose: Adds liquidity to existing Balancer pools, handling token amounts and liquidity tokens minting.

  • Methods:

    • apply(pool, token_in: ERC20, user: str, amount_in: float)

      • Parameters:

        • pool: Pool instance to perform the swap on.

        • token_in: ERC20 token to swap from.

        • user: User address (string) providing liquidity.

        • amt_shares_in: Amount of shares to add.

    • Output: Adds the specified lp amounts to the pool and mints liquidity tokens to the user.

tkn_in = weth
amt_shares_in = 10

res = AddLiquidity(Proc.ADDSHARES).apply(lp, tkn_in, user_nm, amt_shares_in)
lp.summary()

print(f"{amt_shares_in} LP shares were added resulting in an additional {res['tkn_in_amt']} {tkn_in.token_name}")

Balancer Exchange: DAI-WETH (LP)
Reserves: DAI = 9998136.750149786, WETH = 76342.67577167299
Weights: DAI = 0.2, WETH = 0.8
Pool Shares: 110.0295080381873

10 LP shares were added resulting in an additional 8575.921397531378 WETH