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Gas fee access · EVM

Borrow Gas

Help a wallet keep moving when it runs out of transaction fees.

Try the demo How it works
Original Borrow Gas interface showing a 10 AVAX borrowing limit

The original AVAX borrowing interface—not the current swap demo.

My role
Product & engineering
Original product
Wallet-history-based limits
Core technologies
Node.js · EVM · React

Try it here

Borrow Gas, in action.

Open in new tab

Choose Polygon or Solana. This is a capped mainnet prototype with a shared demo wallet, not a lending service. The original product is wound down; the demonstration is a newer implementation.

Use the demo wallet here. For your own wallet, open the demo in a new tab.

Loading the demo. You can also open it in a new tab.

What I built.

The original Borrow Gas product used past gas spending to calculate a borrowing limit. I built the wallet-data services, quote APIs and borrowing interface.

The new demo takes a different approach: swap existing USDC for gas, with no initial native balance and no loan. It runs on Polygon and Solana, separately from the original lending flow.

The skills behind it.

  • Node.js + EVM data

    Read wallet history, calculate gas spending and produce loan quotes in the original product.

  • React + ethers.js

    Connect wallets and present borrowing limits and transaction screens.

  • EVM + Solana

    The current demo adds signed, sponsored swaps with constrained routes, repayment and durable spending limits.

How it works.

  1. Start without native gas

    The demo wallet holds 0.25 USDC and no POL or SOL. A sponsor covers the transaction’s initial gas requirement.

  2. Review and authorise

    The user reviews the amount and minimum output. Real-wallet mode requires their signature; demo mode uses a dedicated server-controlled wallet.

  3. Swap and repay together

    Exchange USDC for native gas and reimburse the sponsor within the transaction. The Solana proof delivered 0.002514415 SOL from 0.25 USDC, starting at zero SOL.