LeventLabs is the independent lab of Levent Ceyhan — netting, settlement and compliance between parties who do not trust each other, where the rule is published in advance, the outcome is committed on a live ledger, and the positions one side would rather not reveal never have to be.
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One product, one market. Everything else on this page is the work it stands on.
Confidential multilateral portfolio compression for OTC derivatives, on the Canton Network. Counterparties tear up offsetting bilateral trades and atomically redistribute their counterparty exposure — while the operator that coordinates the cycle never sees any participant's positions, notionals, or rates.
Compression releases initial margin trapped in offsetting trades — by industry estimates, hundreds of billions of dollars of it. The mechanism has always required handing your entire book to a central operator, which is exactly why most of the buy-side and mid-tier stay out and a large share of compressible exposure is left stranded. CompressRail moves that trust boundary from the operator to the protocol: no operator party is a stakeholder on a position-bearing contract, and every economic field exists on-ledger only as authenticated-encryption ciphertext with no operator-held key.
It runs live against its own Canton DevNet validator (Ledger API 3.5.4) — real party allocation, real encrypted trades, a real matching pass, per-node risk checks and an atomic execute through the global synchronizer. Every privacy claim in the demo is read from that party's own ledger projection rather than hard-coded, and a try to cheat control genuinely attempts, as the operator, to decrypt a participant's book against the live ledger. It fails: the operator's own projection holds zero bilateral trades.
Prior work — each piece carries into CompressRail
Privacy-preserving fraud intelligence for financial institutions. Banks contribute calibrated risk signals to a shared market and benefit from the network's judgement without exposing the customer data underneath it — the collaboration problem compliance teams have wanted solved and could never solve by sharing records.
Carries into CompressRail: the first of two Canton systems built here, and where the thesis started — institutions coordinating on a decision without pooling the inputs behind it.
Confidential compliance attestation for institutional on-chain finance: eligibility, risk and exposure rules enforced over fully encrypted state, revealing only the final eligibility decision. Per-user attributes, issuer policy thresholds and an issuer-wide reserved-exposure aggregate all stay encrypted on-chain, with enforcement FHE-native via FHE.select. Five contracts on Sepolia, 25 passing tests.
Carries into CompressRail: hiding cycle topology means computing over data nobody is allowed to read. AttestRail is that capability already shipped — encrypted state, enforced rules, only the verdict public.
Hosted demo retired after the program; the contracts remain deployed on Sepolia and the addresses are available on request.
I'm Levent Ceyhan, sole founder and engineer. The work is infrastructure for markets where the counterparties do not trust each other — systems where auditability, privacy and provable rules are design primitives rather than afterthoughts.
Most markets that move money run on trust nobody can check. A bank asks another bank to take its word on a risk signal. A dealer hands its entire book to an operator to get a netting cycle computed. In each case one side sees everything, the other either accepts it or walks away, and nothing in between is provable. CompressRail is that problem taken at its most expensive point: compression is a mechanism the derivatives industry already wants and mostly cannot use, for a reason that is structural rather than technical.
Canton matters here because it is the ledger regulated institutions are already adopting, and the one whose privacy model makes an operator-blind cycle possible in the first place. Two Canton systems shipped so far, one of them running live on DevNet with an end-to-end suite that executes against the same public endpoint the demo uses.
Decisions that move money are deterministic, auditable and reproducible. Claims are built so they can be falsified: every privacy figure in the CompressRail demo is read live from a party's own ledger projection, the operator's attempt to read a participant's book is run for real rather than simulated, and the boundary of what is not yet solved is written down next to what is. Where a system acts on its own it acts on published rules with the policy committed on-chain — not on a model's judgement. There is no language model anywhere in a money path shipped here.
The engineering half is Daml and Canton, smart contracts, applied cryptography and confidential compute. Before that, fifteen years on the demand side of performance marketing — Google Ads account strategist, then seven years running performance marketing at Xylem, then independent work in the same field. Long enough spent inside a market where both sides argue from their own dashboards to know why provable beats reported.
Design partners with offsetting exposure, advisors from the derivatives and collateral side, and the ecosystem path to a multi-node pilot. The next engineering milestone is running a cycle across separate participant nodes, then closing topology privacy.
Open to design partners, derivatives-domain advisors and investment conversations — particularly with institutions and market-infrastructure teams that carry offsetting exposure and will not hand their book to an operator to net it.