Atomic Swap
Everything With OASIS

Nimiq’s Open Asset Swap Interaction Scheme (OASIS) is the blueprint that describes how to make off-chain assets such as USD, EUR, stock certificates, web domains and many more behave as if they were tokens on a blockchain.

Who can use Nimiq OASIS

Nimiq OASIS is an open technology. Everyone can use it and implement it. Currently, TEN31 Bank provides an API to their Euro-HTLC implementation, accessible for:

DEXslooking to provide an easy way for users to buy and sell crypto for fiat.

Developerscreating OTC services and applications.

DeFi projectsinterested in creating Crypto-Fiat On/Off Ramps

TEN31 Bank uses OASIS

The German bank, specialized in the emerging blockchain space, is the first party to integrate OASIS into their regulated banking infrastructure.

meet ten31

How does it work?

Nimiq OASIS leverages two established concepts of blockchain-based value transfer: HTLCs and Atomic Swaps.


Hashed Time-Locked Contracts are special smart contracts. They are executed if a certain condition is met or reverted if a certain time period elapses.

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Atomic swap

Atomic Swaps connect two HTLCs by making their execution dependent on each other.

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OASIS is inspired by Interledger's Hashed-Timelock Agreements. These HTLAs (like HTLCs) are conditional payment primitives, a generalization of HTLCs but without ledger support.

Without a ledger, a trusted escrow party is required to enforce the terms of the HTLC. Nimiq OASIS is a framework to implement this enforcement.

Crypto to Fiat Atomic Swap

To start mass adoption, we must enable an easy and secure way into crypto.

Discover how Nimiq OASIS powers a new way of buying crypto, as easy as a bank transfer.

Examine use case Examine use case

For the fiat instantiation, the escrow is a fully-licensed bank which is a trusted node in the fiat currency network. We argue that a licensed bank is more trustworthy than e.g. an unregulated crypto exchange. Except for cash, sending or receiving fiat requires trusting a bank in the first place.

OASIS HTLCs are pre-funded in the sense that the sender needs to give custody of the funds to the escrow party before the contract can be executed. Bilateral (counterparty) risk is eliminated by the trusted escrow party, which takes the place of a decentralized ledger that would enforce the contract's terms if HTLCs were directly supported on-ledger.

To improve decentralization, we envision an ecosystem of OASIS escrow parties, potentially for a wide range of different assets, that users are free to choose from.

Use OASIS to enable merchants to accept crypto while receiving fiat.

OASIS allows merchants to accept crypto, like NIM or BTC, while receiving fiat like Euro directly to their bank account.

Use OASIS to provide cheap and non-custodial remittances.

Nimiq OASIS is an almost universal concept able to exchange virtually any digital asset. Besides exchanging crypto for fiat, it can also leverage and apply the advantages of blockchain technology to fiat/fiat swaps.

Imagine atomic-swapping Euro for Dollar, Dollar for Yuan, or Yuan for Rupee.

A remittance provider can request fiat HTLCs from two banks that have implemented Nimiq OASIS. Alice funds the HTLC provided by her bank and releases currency to the remittance provider. By doing so, Bob can claim the equivalent value in his currency, using the HTLC provided by his bank and funded by the remittance provider.

Integrate Nimiq OASIS

Nimiq OASIS is an open technology and is accessible to everyone.

OASIS Implementation

  • OASIS escrow party provides a permissionless API to enable any decentralized application to interact with OASIS contracts.

  • Users never directly interact with the OASIS API, but always through application integrations.

  • The escrow party is bound by the HTLC it provides through the API. As such it serves as a trusted party to secure the funds and execute the settlements.

  • Applications use the OASIS API to prepare, audit and settle contracts.

  • A user clears a contract by transferring the necessary funds to the escrow party.

Resources and documentation

The team put together useful resources and links to guide any implementation and integration. Reach out to us for assistance and other inquiries.

TEN31 case study

Read all about the collaboration of TEN31 and Nimiq.

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Visit TEN31’s OASIS site to access the API and its description.

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SandBox testing environment

Test your own OASIS integration in our secure sandbox environment.

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Technical Documentation

Browse the Nimiq OASIS documentation and libraries.

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Max Burger, Nimiq Ambassador

Max Burger

Nimiq Ambassador
Contact Max
Talk to a Nimiq expert

Collaborate with Nimiq and integrate OASIS.

Team Nimiq offers dedicated service and support for strategic partners. Get in contact and be one of the first to leverage a new paradigm in value transfer.

How does Nimiq OASIS benefit the Nimiq Ecosystem?

Nimiq OASIS solves a fundamental problem: Until now, easy and low-fee buying and selling of crypto for fiat money (EUR/USD) without setting up exchange accounts remained a critical problem to solve to reach mass adoption. With Nimiq OASIS, buying crypto will be one simple bank transfer, with the corresponding crypto-delivery guaranteed to your wallet.

The more OASIS is used, the more NIM is used: Every time someone transacts via OASIS a 1% fee applies for the use of the OASIS API. For at least the first 24 months from its official launch, the collected fees are used to buy NIM off the market, which then are held by the Nimiq Foundation to increase scarcity and for the future benefit of the project.

Nimiq OASIS also creates additional revenue opportunities: Nimiq is developing the FAST (Fiat Atomic Swap Trader) Service. FAST acts as Market Maker and will ensure liquidity for Nimiq OASIS instantiations, such as the TEN31 implementation.

The information stated on this website is provided for information purposes and must not be construed as a binding agreement between Nimiq and the user. Users that access these services either through an API or through the deployment of an HTLC agree to be bound by the terms of service provided therewith. All rights reserved and copyright owned by Nimiq Foundation.