Ethereum Upgrades and Layer 2 Scaling 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 Ethereum Upgrades and Layer 2 Scaling flashcards as text
What is the upgradeable proxy pattern in Solidity development?
Answer: A design where a proxy contract delegates calls to an implementation contract that can be swapped
The upgradeable proxy pattern separates storage (proxy) from logic (implementation), allowing the logic to be replaced without losing state.
What is a storage collision problem in upgradeable proxy contracts?
Answer: When the proxy and implementation use the same storage slots, causing data corruption during upgrades
Storage collision occurs when the proxy contract's own variables occupy the same storage slots as the implementation's variables, corrupting state.
What is Ethereum's EVM (Ethereum Virtual Machine)?
Answer: A sandboxed runtime environment that executes smart contract bytecode on every Ethereum node
The EVM is a stack-based virtual machine that executes bytecode deterministically on all nodes, ensuring consistent contract execution across the network.
What is gas in Ethereum and why does it exist?
Answer: A unit measuring computational work, preventing infinite loops and spam by requiring payment for execution
Gas quantifies EVM computation cost, ensuring users pay for resources used and preventing denial-of-service attacks via infinite loops.
What is the purpose of the `SELFDESTRUCT` opcode in Solidity (pre-Cancun)?
Answer: To destroy the contract and send its remaining ETH balance to a specified address
`SELFDESTRUCT` (now deprecated in EIP-6780) would remove contract bytecode and forward the ETH balance to a target address.
What is Ethereum's 'difficulty bomb' and why was it introduced?
Answer: A mechanism that exponentially increased mining difficulty to encourage the transition to Proof of Stake
The difficulty bomb gradually increased Proof of Work mining difficulty to make PoW economically unviable and pressure the network toward the Merge.