Order visibility
On a standard AMM or order book, the size and direction of a pending trade is visible in the mempool or the book itself, exposing traders to front-running and adverse price movement before their own transaction even confirms.
Enclave · Built on Arc
Private, verifiable stablecoin trading on Arc.
Enclave is a trading protocol that lets anyone exchange stablecoins — starting with USDC and EURC — privately, with settlement finality guaranteed by cryptography rather than by trust in an operator.
Stay private.
- Trusted parties required
- 0
- Balance-backed custody
- 100%
- Native gas on Arc
- USDC
Enclave is built on infrastructure the market already trusts
- Arc
- Circle
- USDC
- EURC
- AWS Nitro
- Succinct SP1
- Chainlink
Abstract
Trust is replaced, not required
Order execution happens inside a hardware-attested Trusted Execution Environment (TEE), and every batch of trades is independently re-proven correct by a zero-knowledge virtual machine (zkVM) before any fund moves on-chain. No custodian, exchange operator, or market maker ever needs to be trusted to execute an order faithfully or to keep a customer's position confidential — both properties are enforced by code that anyone can inspect and verify.
Enclave is built on Arc, Circle's Layer-1 blockchain purpose-built for stablecoin finance, combining Arc's institutional-grade settlement infrastructure with a privacy and correctness architecture that has no dependency on any single trusted party.
1. The Problem
Stablecoin FX still runs on trust
Stablecoins have become the dominant medium for on-chain value transfer, but trading between them — stablecoin FX — still largely inherits the trust assumptions of traditional exchanges.
Operator trust
Centralized or semi-centralized venues ask users to trust that the matching engine executed their order at the price and time claimed — an assertion, not a proof.
Custody risk
Funds routed through an intermediary account are, for the period they sit there, an IOU backed by the intermediary's solvency, not a cryptographic guarantee.
Enclave is designed to remove all three trust assumptions simultaneously, without giving up the speed and liquidity access users expect from a real trading venue.
2. Design
TEE for speed, ZK for finality
Every order in Enclave follows the same two-stage pipeline:
Private execution (TEE)
The trader's order is encrypted directly to the public key of a specific, hardware-attested enclave (AWS Nitro). Only that enclave can decrypt it; the operator relaying the ciphertext never sees the order's size, side, or the trader's strategy. The enclave executes the trade against the live, on-chain oracle price and returns a result in seconds.
Cryptographic finality (ZK)
The identical execution is independently re-proven inside a Succinct SP1 zero-knowledge virtual machine. The resulting proof is verified on-chain by a dedicated verifier contract before any settlement is accepted. If the enclave's execution and the proof ever disagreed — whether from a bug, a compromised enclave, or a dishonest operator — the proof simply could not be produced for a false result. There is no code path that allows a trade to settle on the enclave's word alone.
This split is deliberate: the TEE gives traders a private, fast preview; the zero-knowledge proof is what actually authorizes value to move. Trust is never required — it is replaced by hardware attestation on one side and cryptographic verification on the other, both independently checkable by any third party.
3. Custody
Real balances, never IOUs
All funds are held by a single custody contract, the Enclave Vault. Its guiding invariant is simple to state and strictly enforced in code:
No withdrawal may ever be authorized for more than the Vault's real, on-chain, unreserved balance of that asset — for any trade, under any circumstance.
Deposit-bound settlement
A trader's deposit is tied to a real ERC-20 transfer and a commitment they choose; it is only ever consumed by a settlement whose proof discloses exactly how much of that deposit funded a given trade.
Unconditional solvency checks
Every settlement's solvency check runs unconditionally, with no exception for edge cases — a batch that would leave any withdrawal under-collateralized reverts atomically, in its entirety, rather than creating a pending, unfunded claim.
Self-service recovery
If a deposit is ever left unconsumed because its paired trade could not settle, the depositor — and only the depositor — can recover it directly from the contract after a fixed timeout. No operator, relayer, or administrative key is involved in that recovery path.
Formula-driven liquidity
Liquidity providers supply the inventory a trade settles against and are compensated by a transparent, on-chain market-making formula (base spread + realized volatility + utilization) — never a discretionary, off-chain-set price.
4. Price Integrity
On-chain, manipulation-resistant, stable under proving time
Every trade is priced against a live price feed read directly from a decentralized Chainlink oracle — not a signed off-chain feed, not an API call to a centralized price source.
The feed's native 8-decimal answer is scaled to 18 decimals before it ever reaches the pricing formula, and that same scaled value feeds both the UI and the guest zkVM program, so the two can never disagree on what price a trade was proven against. Because zero-knowledge proof generation takes real wall-clock time, the oracle's reported price is anchored to fixed time buckets rather than drifting every block, so the price a trade proves against cannot silently change out from under it while its proof is being generated. The market-making formula itself — spread, volatility term, utilization skew — is recomputed and enforced inside the same zero-knowledge proof, so the executing party has no discretion to quote a trader a worse price than the formula allows.
5. Compliance
Compliance without silent access
Enclave includes an optional, purpose-built compliance mechanism that resolves the usual tension between privacy and regulatory accountability: every trade can produce a sealed, encrypted record of its counterparties, decryptable only through a process that requires a matching, permanent, public entry on-chain first.
Anyone — not just a regulator, not just the operator — can independently verify, at any time, whether that decryption key has ever actually been used, and exactly when and why. The guarantee is not absolute secrecy from all parties; it is that access is never silent, never undocumented, and never something a user has to take on faith.
6. Why Arc
Purpose-built for stablecoin finance
Enclave is built on Arc, Circle's Layer-1 blockchain, because its design goals line up almost exactly with what a serious stablecoin trading venue needs:
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Stablecoins as native gas
Transaction fees on Arc are paid in USDC itself — there is no separate, volatile gas token whose price swings distort the true cost of a trade. Fee predictability that matters for a trading protocol is a first-class property of the chain, not something built on top of it.
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Deterministic, sub-second finality
Arc's consensus is engineered for real-time settlement, not probabilistic confirmation. Combined with Enclave's own oracle-anchoring design, this makes the window between "trade proven" and "trade final" as short as the underlying chain allows.
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Institutional-grade validators and compliance tooling
Arc's founding validators include major financial infrastructure players (asset managers, global banks, payment networks), and the chain ships with integrated compliance and transaction-monitoring tooling out of the box — infrastructure a trading venue would otherwise have to build or bolt on itself.
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Real, liquid stablecoin markets already on-chain
USDC and EURC are native, first-class assets on Arc with confirmed, real liquidity — including genuine Uniswap V3 pools with real trading volume — not synthetic placeholders awaiting adoption.
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No dependency on a third party choosing to support Arc
Enclave's zero-knowledge verifier is an open-source contract deployed directly by the protocol itself, not a service that has to be officially provisioned by an external prover network for a given chain. Bringing the full privacy-and-proof pipeline to Arc required no permission and no external rollout — only a standard contract deployment.
7. Verifiability
Verifiability by design
Every trust-sensitive claim Enclave makes is independently checkable, without cooperation from the operator:
Enclave authenticity
Anyone can rebuild the published enclave image from source, compare its measurement against the live enclave's own signed attestation, and confirm the encryption key a trader submits an order to is cryptographically bound to that exact, unmodified instance.
Settlement correctness
A successful settlement transaction is only possible if a valid zero-knowledge proof was verified on-chain; this can be confirmed by reading the transaction receipt directly, with no special access.
Unlinkability
A completed trade's deposit and withdrawal share no on-chain edge; this is a property of the transaction graph itself, checkable by anyone scanning the chain.
Compliance access
Whether a compliance record has ever been decrypted is a public, permanent fact anyone can query directly from the relevant contract's event log.
Nothing above requires trusting a claim on this page — it requires only an RPC endpoint and the open-source verification tooling that ships alongside the protocol.
8. Summary
Neither privacy nor security require trusting an operator.
Private execution is hardware-attested, correctness is zero-knowledge-proven, custody is balance-backed with no IOUs, pricing is on-chain and formula-enforced, and compliance access is publicly auditable rather than silently granted.
Built on Arc, it inherits a settlement layer already engineered for exactly this kind of institutional-grade, stablecoin-native financial activity — real liquidity, predictable fees, and deterministic finality — without asking any user to take a single claim on faith.