eFIN DEX added crypto-fiat swaps support powered by SuperSimpleSwap and Nimiq OASIS

Reading Time: 2 minutes ;  Published: 1 year ago on March 30, 2022

SuperSimpleSwap performs non-custodial atomic swaps between crypto and fiat using the OASIS protocol, developed by Nimiq, a cryptocurrency and crypto payment system combining true decentralization and everyday ease-of-use.


Getting Started

In order to perform a fiat (EUR) to crypto (BTC, BEP-20) atomic swap using the eFIN DEX and SuperSimpleSwap you'll need:

  1. The eFIN wallet (the latest release can be found at https://github.com/eFIN-DEX/efin-builds/releases).
  2. A SEPA bank account capable of instant transfers (specifically “SCT Inst, EBA RT1”).
  3. Not have exceeded the 30 days total swap limit (USD 1000 at the time of writing).

All swaps are non-custodial

SuperSimpleSwap and the protocol Nimiq OASIS are fully automated systems. The fiat money (EUR) you sent will be automatically refunded to your bank account if the swap is not completed. Remember that all atomic swaps would either happen as planned or it is reversed after timing out or failing and both swapping parties automatically receive back their assets. In any case always keep the displayed swap ID in case you need of support.

With non-custodial wallets, DEXs or services like SuperSimpleSwap you have full control over your funds and the associated private key (“Your keys, your coins”). That means you are not giving up control of your funds until it is guaranteed that you receive the other asset you are swapping them for. On the crypto side of the swap for SuperSimpleSwap, this is enforced through cryptographic smart contracts (HTLCs); and on the fiat side of the swap, through programmatic, verifiable commitment by the independent EUR HTLCs provider (ie. TEN31 Bank).

BTC network fees could be significant

As SuperSimpleSwap relies on two near-instant on-chain transactions for both HTLCs (in and out), fees are chosen such that the transaction is confirmed within the next block. Depending on the current usage of the network, Bitcoin network transaction fees can easily be EUR 10 or higher. The Bitcoin network usage varies over time and usually is lower on weekends, allowing for cheaper swaps at certain times. This also demonstrates the advantages of Nimiq OASIS as a next generation blockchain protocol where network transaction fees and thus fees for an atomic swap with BEP-20 are close to zero.

Be aware of the limits

The amount you can swap might automatically adjust to the maximum allowed based on the 30 day moving window limit. Any swap attempt, it doesn’t matter if the swap succeeded, failed or was manually cancelled, will be deducted from your available limits to protect the system against atomic swap spam attacks.

If you bank account doesn't support instant wire transfers it can take up to 5 business days to reflect the received amount in your bank account balance. If you provided a wrong or invalid IBAN number yoy'll need to follow the steps provided on the eFIN website to provide a different IBAN address. Also, if the recipient bank account reached its 30 day rolling swap limit you should automatically receive the deposit after the time limit frees up.

Where can I find mor information about SuperSimpleSwap and eFIN DEX?

You will find the official FAQ with detailed information about SuperSimpleSwap and the eFIN DEX at the eFIN website here.