All terms
A rollup that proves every batch is valid using cryptography.
ZK rollups generate a validity proof for each batch. The layer 1 verifies the proof, so there is no need for a challenge period and withdrawals can be fast.
The cost is complexity. Generating proofs is computationally expensive, and building a proving system that handles arbitrary EVM code took years.
zkSync Era, Starknet, Scroll and Linea are ZK rollups.
That the proof means there is nothing to trust. The math is checkable, and the sequencer, the upgrade keys and the prover setup are still run by people. Validity proofs remove one large assumption and do not remove all of them.
Common questions
Does zero knowledge mean my transactions are private?
Why are ZK rollups harder to build?
Where this comes up on the site
The guides that actually use this word, rather than a list of everything we have written.
Where to go next
More technology terms
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