Web3.js, Ethers.js and Ethereum APIs Flashcards
6 cards from real Ethereum Developer practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Web3.js, Ethers.js and Ethereum APIs flashcards as text
What is Hardhat used for in Ethereum development?
Answer: A development environment for compiling, testing, and deploying Solidity smart contracts
Hardhat is a popular Ethereum development framework that provides a local blockchain, testing tools, and deployment scripts.
What is the purpose of Foundry's `forge test` command?
Answer: To run Solidity-native unit tests written directly in Solidity
`forge test` runs test contracts written in Solidity using Foundry's testing framework, providing fast and native EVM-level testing.
What does `eth_estimateGas` return?
Answer: An estimate of the gas required to execute a given transaction
`eth_estimateGas` simulates a transaction and returns an approximate gas cost without submitting it to the network.
What is an Ethereum node's RPC endpoint used for?
Answer: As an HTTP or WebSocket interface to send JSON-RPC requests to the node
The RPC endpoint exposes a standardized JSON-RPC API that lets applications query blockchain state and submit transactions.
What does the `chainId` field in an EIP-155 transaction prevent?
Answer: Replay attacks where a transaction signed for one network is resubmitted on another
EIP-155 added `chainId` to the transaction signature to prevent a valid Ethereum mainnet transaction from being replayed on testnets or other EVM chains.
What is the purpose of `IPFS` in the context of NFT development on Ethereum?
Answer: Decentralized storage for NFT metadata and media files referenced by token URIs
IPFS stores NFT images and metadata off-chain in a content-addressed, decentralized manner, with the content hash stored on-chain as the token URI.