@backchain/buyback

Proof-of-Purchase mining module for the Backchain DeFi ecosystem on opBNB.

Install

npm install @backchain/buyback

Quick Start

import { createContext } from '@backchain/core';
import { BuybackModule } from '@backchain/buyback';

const ctx = await createContext({ provider, signer });
const buyback = new BuybackModule(ctx);

const preview = await buyback.preview();
console.log('BKC to buy back:', preview.bkcOut);
const tx = await buyback.execute();

API

Write Methods

execute(): Promise<TransactionResponse>

Triggers the buyback: uses accumulated BNB fees to buy BKC from the LP, then burns or distributes the BKC. The caller earns a 5% execution reward.

executeWithSlippage(minBkcOut: bigint): Promise<TransactionResponse>

Same as execute() but with an explicit minimum BKC output guard. Reverts if slippage exceeds the specified threshold.

Read Methods

preview(): Promise<BuybackPreview>

Simulates the next buyback execution. Returns estimated BKC output, caller reward, and amount to be burned.

pendingEth(): Promise<bigint>

Returns the total BNB accumulated and available for the next buyback execution.

miningRate(): Promise<bigint>

Returns the current mining rate (BKC distributed per unit of BNB spent on buyback).

getExecutionFee(): Promise<bigint>

Returns the BNB fee required to call execute().

getSupplyInfo(): Promise<SupplyInfo>

Returns current BKC total supply, circulating supply, and total burned to date.

getStats(): Promise<BuybackStats>

Returns historical buyback statistics: total BNB spent, total BKC burned, number of executions.

getLastBuyback(): Promise<LastBuyback>

Returns block number, timestamp, BNB used, and BKC burned from the most recent buyback execution.

Notes

• Accumulated BNB fees originate from ecosystem protocol fees.
• Caller reward is 5% of the BKC purchased in that execution.
• All amounts are bigint (ethers.js v6 wei scale).

License

MIT