Glossary

Terp — Cosmos-SDK chain that hosts private notes and the Private DEX settle contract.

Private DEX — Research product for shielded swaps on Terp: spend private notes, update public AMM reserves, mint private notes out.

Shielded swap — One settle action that consumes private input notes and creates private output notes while applying a public reserve update.

Private note — Committed balance whose amount and owner stay private; the commitment (and nullifier on spend) is what observers see.

Commitment — Public leaf that binds a note without revealing its opening.

Nullifier — Public spent marker derived on spend so the same note cannot spend twice.

Virtual AMM — Automated market maker whose liquidity is public reserve counters, not custody of note openings inside the pool.

Public reserves — Transparent (R_A), (R_B) (or oriented in/out) balances on a pool, updated only by valid proven actions.

Pool — Public pair record: assets, reserves, fee factor, status (Active or Paused).

Constant-product quote — Exact-in formula that prices delta_out from reserves and gamma / gamma_den.

min_out — Trader slippage floor; settle rejects when the quote is lower.

Oracle mid — Attested reference price used only as an acceptance band (freshness + slippage). Never a mint authority.

Hub — Center asset in the v1 star topology; demo edges are two demo tokens each trading against one hub token.

cBTC-class unit — Demo or fixture denomination shaped like wrapped Bitcoin; not a frozen mainnet asset listing on this research surface.

Verifying key — Public parameters for proof verification, registered under a circuit id (zkid) when real verify is on.

Change note — Optional private output that returns unused input asset when input notes exceed delta_in.

Settle — On-chain accept of a public swap statement (and proof path): nullifiers inserted, commitments appended, reserves updated.

CosmWasm — WebAssembly smart-contract runtime used on Cosmos chains, including Terp.

Claim — Separate private-note mint path (often airdrop-style) that shares the note set with bridge mint and swaps.

Halo2 — Zero-knowledge proving system referenced for production swap circuits when mock verify is off.

zk host import — Chain-host API that verifies proof bytes against a registered verifying key (zkid).

mock_verify — Lab verify mode that accepts a non-empty proof after host seam checks; not a production proving system.

Fail closed — Reject settle when required verification or seam checks cannot run; no silent success.

Private Bridge — Separate research product that admits value into private notes; not the swap venue documented here.