Glossary

Account

A Zeko L2 account is identified by a public key and token ID. Its public key uses the B62... format. Ethereum accounts use 0x... addresses. On the Ethereum-backed Zeko deployment the native balance is ETH; custom tokens have separate token accounts.

Account Update

An instruction to change one Zeko account, subject to preconditions and authorization. A zkApp transaction contains one or more AccountUpdate values. This is part of the Mina-derived execution model retained by Zeko.

Actions

Append-only messages authenticated by an action-state commitment. Ethereum deposits become Zeko outer actions through a bridge proof; L2 withdrawal actions become settlement-bound claim commitments. See Core Concepts.

Asset Registry

The authenticated mapping between an Ethereum ERC-20 and its Zeko token identity, precision, and bridge configuration. A matching token symbol alone does not establish this mapping.

Blockchain

A sequence of cryptographically linked blocks whose accepted state is determined by consensus rules.

Consensus Mechanism

Rules by which a network agrees on its accepted chain and state. Ethereum uses proof of stake.

Cryptography

Mathematical techniques used for signatures, commitments, hashes, and proofs that protect and authenticate protocol data.

Custom Tokens

Tokens represented by separate token accounts on Zeko. o1js provides TokenContract for implementing token permissions and operations. Only registered mappings are supported for ERC-20 bridging.

Data Availability (DA) Layer

Storage and retrieval of the data needed to reconstruct rollup state. The current Ethereum testnet uses a 2-of-3 DA committee. Complete Ethereum blob publication and blob-to-batch-root binding remain future work.

Decentralisation

Distribution of operation and control among independent participants. Zeko's current Ethereum integration retains permissioned operational and administrative roles.

ETH

Ether, the native asset of Ethereum and the Ethereum-backed Zeko deployment. ETH has 18 decimals on Ethereum and 9 on Zeko; software must convert units at the bridge boundary.

Finality

The point at which a chain treats an accepted block as finalized under its consensus rules. L2 inclusion is distinct from Ethereum settlement and Ethereum finality.

Layer 1 (L1)

The base chain where a rollup settles. For the current Zeko architecture, this is Ethereum.

Layer 2 (L2)

The execution layer that batches transactions and settles results on L1. Zeko's L2 uses a zkApp ledger and recursive proofs.

Merkle Tree

A commitment structure that permits efficient inclusion proofs. Ethereum withdrawal claims use a Merkle path under a settlement-bound claim root.

Mina Protocol

The source ecosystem for Zeko's inherited ledger, zkApp, address, and Pickles/Kimchi proof foundations. It is the settlement chain of legacy Zeko deployments, not the Ethereum-backed deployment. See Proof-System Heritage.

Permissions

Account rules specifying which changes require a signature, proof, or other permitted authorization. zkApp account updates must satisfy these rules and their preconditions.

Proof of Stake (PoS)

A consensus mechanism using staked assets and validator participation to secure a chain. Ethereum uses proof of stake.

Proof of Work (PoW)

A consensus mechanism in which miners perform computational work to propose blocks. Bitcoin uses proof of work.

Prover / Verifier

A prover constructs evidence for a statement; a verifier checks it. Zeko proof workers establish valid L2 transitions, and the SP1 settlement program verifies the exported proof for Ethereum.

Recursion

Verification of one proof inside another. Zeko uses Pickles recursion to aggregate transaction and rollup proofs.

Reducer

An o1js construct for dispatching and processing actions in a zkApp. Actions and their commitments let contracts authenticate ordered messages.

Sequencer

The service that orders transactions, applies them to the Zeko ledger, writes DA data, schedules proofs, and prepares commits for settlement.

Settlement

Acceptance of a proof-bound Zeko state transition by the Ethereum settlement contract. A submitted settlement transaction is not yet a finalized Ethereum checkpoint.

Smart Contract

Code defining authorized changes to blockchain state. Zeko applications use zkApps; Ethereum settlement and custody use Solidity contracts.

SP1

The zkVM used by the Ethereum integration to verify Zeko proofs and produce proof-backed settlement and bridge receipts that Ethereum contracts can verify.

Token Account

A balance and associated state for a public key under a particular token ID. See Account.

Token ID

An identifier for a Zeko token. It is distinct from an Ethereum ERC-20 contract address and must be resolved through the registry when bridging.

Token Manager Account

See Custom Tokens.

Token Owner

The zkApp account that defines authorization for a custom token, including minting, burning, and approving transfers.

TokenContract Class

The o1js base class for implementing custom token contracts on the zkApp execution layer.

Transaction Snark

A proof of a ledger state transition. Recursive aggregation combines these proofs into a proof for a batch of transactions.

Zero-Knowledge Proof (ZKP)

A proof that establishes a statement without revealing its private witness. Public outputs and published transaction data remain visible.

Zeko

An Ethereum rollup for zero-knowledge applications. It retains the Mina-derived zkApp execution model and settles proof-bound state through SP1 and Ethereum contracts.

Zeko Snap

The MetaMask Snap that provides a Zeko L2 account and approves Zeko signatures. It complements the Ethereum account in MetaMask. Local Snap development uses MetaMask Flask; availability in ordinary MetaMask depends on release and allowlisting status.

zkApp

A zero-knowledge application using provable methods and account updates. Zeko zkApps are written with o1js; developers choose which inputs stay private and which state is public.

ZkProgram

An o1js construct for provable off-chain computation, including recursive programs whose proofs can be verified by a zkApp.

zk-Rollup

A Layer 2 design that batches transactions and proves their validity to a settlement chain. Proof validity, data availability, finality, and administrative control are separate parts of the security model.