Blockchains

What are EVM-compatible chains? Any blockchain that is compatible with Ethereum. There are over 300 chains, including Base, Optimism, Arbitrum, and Polygon. Loop supports any EVM-compatible blockchain, including Solana and Tron. You can find a list

here of all EVM-compatible chains but please reach out if you have any questions.

What are network (chain) IDs? Each blockchain has it's own ID that is used so we know where to send the transaction. You can find network IDs

here.

Tokens

Most, if not all tokens on EVM compatible chains are ERC-20 tokens. Example tokens are USDC, USDT and Dai. A network's native token (e.g. ETH, SOL, MATIC) is not ERC-20 and USDT on Ethereum is not fully ERC-20 compliant. Wrapped versions of native tokens exist which are ERC-20 (e.g. wETH, wSol, wMatic).

Loop works with one-time payments for any token type and subscriptions only with ERC-20 and SPL (on Solana).

Wallets

What is the difference between a non-custodial and a custodial wallet?

A custodial wallet is one where the end user does not hold the private keys. Almost all exchanges are custodial (e.g. Coinbase, Binance, Kraken, OKx), however most of these exchanges have a non-custodial wallets that users can also use (e.g. Coinbase Wallet, OKx Wallet). All browser extension wallets (e.g. Metamask) are non-custodial.

Currently Loop only supports non-custodial wallets but we are adding functionality for custodial wallets. If you'd like this functionality, please reach out to use at [email protected]

Testnets

Most blockchain networks have testnest. Sepolia is widely used for EVM-compatible chains and DevNet for Solana.

To transact on these chains, you will need ETH or SOL for gas and USDC has a payment token. You can get these for free from using faucets.

ETH Faucets: Sepolia-Faucet, Quicknode Sepolia Faucet, Chainlink Sepolia Faucet
Sol Faucet: Solana DevNet Faucet USDC Faucet: USDC (has the option to get on both Ethereum and Solana)