Lending Pools

One lending-pool implementation serves four configured frontend markets: XLM, Blend USDC, Aquarius USDC, and Soroswap USDC. Each deployment has its own underlying asset, liquidity, debt shares, and vToken.

Supply and redeem

deposit(lender, amount_wad) authenticates the lender, accrues interest, transfers native underlying, and mints vTokens. The first deposit uses 1:1 WAD accounting and reserves 1,000 WAD share units for minimum liquidity before native vToken conversion. Later deposits use a virtual offset of 1 WAD integer unit in both supply and assets. A zero-share accounting result is rejected. redeem_vtokens(lender, tokens_to_redeem_wad) accepts vToken quantity in WAD, not underlying quantity or raw native receipt units. Payout is clamped to the minimum of requested value, 50% of total assets, and available liquidity. A partial redemption burns the recomputed share amount; zero available payout fails. Read the event’s asset_amount and remaining balance to determine what actually redeemed.

Borrow and repay accounting

Only AccountManager may call lend_to and collect_from. lend_to returns (is_first_borrow, net_amount_wad) on success, records gross debt with upward-rounded shares, and distributes the fee to treasury and net proceeds to the SmartAccount. New borrowing cannot exceed 95% pool utilization. collect_from updates debt accounting; it does not itself pull tokens. AccountManager’s regular repay path separately transfers account-held underlying, while liquidation transfers from the liquidator using an allowance. Do not call the pool accounting function as a standalone repayment flow. get_borrows includes pending interest with floor rounding. update_state persists interest with ceiling rounding. Account debt getters use these live preview borrows, not just stored principal. See Math Reference.

Pool administration

Pool pause blocks supply, redeem, and borrow, but not collect_from. Admin transfer is two-step. Origination fee and rate-model address are configurable. Read get_origination_fee rather than assuming a fixed deployment fee. The frontend’s 0.9999 spend buffer is a rounding allowance, not the on-chain fee.

Function signatures

These signatures are copied from the reviewed Rust implementation. env is supplied by Soroban and is not a transaction argument. Result errors and panics must be handled by the caller; simulation does not guarantee later execution. Public methods include privileged and internal-contract callbacks, not just user entrypoints.

__constructor

pub fn __constructor(
        env: Env,
        admin: Address,
        asset_config: AssetConfig,
        registry_contract: Address,
        account_manager: Address,
        rate_model: Address,
        token_issuer: Address,
        treasury: Address,
        origination_fee: U256,
    )

propose_admin

pub fn propose_admin(env: Env, proposed: Address) -> Result<(), LendingError>

accept_admin

pub fn accept_admin(env: Env) -> Result<String, LendingError>

get_admin

pub fn get_admin(env: &Env) -> Result<Address, LendingError>

initialize_pool

pub fn initialize_pool(
        env: Env,
        vtoken_contract_address: Address,
    ) -> Result<String, LendingError>

deposit

pub fn deposit(env: Env, lender: Address, amount_wad: U256)

redeem_vtokens

pub fn redeem_vtokens(env: &Env, lender: Address, tokens_to_redeem_wad: U256)

lend_to

pub fn lend_to(
        env: &Env,
        smart_account: Address,
        amount_wad: U256,
    ) -> Result<(bool, U256), LendingError>

collect_from

pub fn collect_from(
        env: &Env,
        amount_wad: U256,
        trader_smart_account: Address,
    ) -> Result<bool, LendingError>

convert_asset_borrow_shares

pub fn convert_asset_borrow_shares(env: &Env, amount_wad: U256, round_up: bool) -> U256

convert_borrow_shares_asset

pub fn convert_borrow_shares_asset(env: &Env, debt_wad: U256) -> U256

update_state

pub fn update_state(env: &Env)

set_paused

pub fn set_paused(env: Env, paused: bool)

is_paused

pub fn is_paused(env: &Env) -> bool

before_deposit

pub fn before_deposit(env: &Env)

before_withdraw

pub fn before_withdraw(env: &Env)

get_user_borrow_shares

pub fn get_user_borrow_shares(env: &Env, trader: Address) -> U256

get_borrow_balance

pub fn get_borrow_balance(env: &Env, trader: Address) -> U256

get_total_borrow_shares

pub fn get_total_borrow_shares(env: &Env) -> U256

total_assets

pub fn total_assets(env: &Env) -> U256

get_borrows

pub fn get_borrows(env: &Env) -> U256

get_rate_factor

pub fn get_rate_factor(env: &Env) -> Result<U256, InterestRateError>

get_total_liquidity_in_pool

pub fn get_total_liquidity_in_pool(env: &Env) -> U256

get_last_updated_time

pub fn get_last_updated_time(env: &Env) -> u64

get_current_total_vtoken_balance

pub fn get_current_total_vtoken_balance(env: &Env) -> U256

get_total_vtokens_minted

pub fn get_total_vtokens_minted(env: &Env) -> U256

get_total_vtokens_burnt

pub fn get_total_vtokens_burnt(env: &Env) -> U256

get_lenders

pub fn get_lenders(env: Env) -> Vec<Address>

is_pool_initialised

pub fn is_pool_initialised(env: &Env) -> bool

get_native_asset_address

pub fn get_native_asset_address(env: &Env) -> Address

get_asset_config

pub fn get_asset_config(env: &Env) -> AssetConfig

convert_asset_to_vtoken

pub fn convert_asset_to_vtoken(env: &Env, amount_wad: U256) -> U256

convert_vtoken_to_asset

pub fn convert_vtoken_to_asset(env: &Env, vtokens_to_be_burnt_wad: U256) -> U256

update_origination_fee

pub fn update_origination_fee(env: &Env, origination_fee: U256)

update_rate_model

pub fn update_rate_model(env: &Env, new_rate_model: Address)

get_origination_fee

pub fn get_origination_fee(env: &Env) -> U256

get_treasury

pub fn get_treasury(env: &Env) -> Address

get_max_utilization_wad

pub fn get_max_utilization_wad(_env: &Env) -> u128

upgrade

pub fn upgrade(env: &Env, new_wasm_hash: BytesN<32>)

Source reference

Protocol_V1_Soroban_testnet/contracts/lending-pool/src/pool.rs

​Supply and redeem

​Borrow and repay accounting

​Pool administration

​Function signatures

​__constructor

​propose_admin

​accept_admin

​get_admin

​initialize_pool

​deposit

​redeem_vtokens

​lend_to

​collect_from

​convert_asset_borrow_shares

​convert_borrow_shares_asset

​update_state

​set_paused

​is_paused

​before_deposit

​before_withdraw

​get_user_borrow_shares

​get_borrow_balance

​get_total_borrow_shares

​total_assets

​get_borrows

​get_rate_factor

​get_total_liquidity_in_pool

​get_last_updated_time

​get_current_total_vtoken_balance

​get_total_vtokens_minted

​get_total_vtokens_burnt

​get_lenders

​is_pool_initialised

​get_native_asset_address

​get_asset_config

​convert_asset_to_vtoken

​convert_vtoken_to_asset

​update_origination_fee

​update_rate_model

​get_origination_fee

​get_treasury

​get_max_utilization_wad

​upgrade

​Source reference