Cost-effective protocol to accept crypto payments across EVM-compatible blockchains.


To accept crypto payments, crypto exchanges and other crypto-friendly services usually allocate a unique proxy wallet (aka deposit address) for each end-user. Due to architecture of EVM blockchains, all assets deposited by end-users into proxy wallets must be forwarded to the Omnibus wallet for further management.
Although exchanges do not charge end-users any fees for incoming payments, exchanges and any other custodial service incur a base cost to transfer assets to the Omnibus (Hot Wallet), accepting crypto payments.
The well-established implementations of crypto processing typically costs between 63,000 to 120,000 Gas for each incoming token payment.
Gas usage is just one of the issues with this commonly used approach.
Managing residue on proxy wallets, maintaining infrastructure, estimating gas costs, implementing custom refund rules, supporting new tokens and asset standards, and many other challenges require businesses to either develop complex in-house infrastructure or incur high fees for third-party services to make it work.

Solution overview

We started Curra with an idea of creating solution to accept crypto payments without intermediaries, thus we pioneered new approach to make in non-custodial.
Through smart contracts within the Vortex, we guarantee that all the proxy wallets and assets on them belongs solely to you with no intermediaries involved.
To achieve this we created architecture that consist of:

Efficient Gas consumption

Along with non-custodial nature of Vortex, this architecture allowed us to create the most gas-efficient solution on the market.
Solidity Assembly, bundled transactions, and contract factories at Vortex provides up to 75000 Gas savings on each incoming transaction.
Which saves ~$63,300 in equivalent of ETH for each 10,000 incoming payments.
With Vortex we offer a cost-effective, non-custodial, and flexible solution to manage incoming payments and proxy wallets.
Gas Usage
Cost of incoming payment
~ 11,000 Gas
$ 0.95
~ 63,000 Gas
$ 5.46
~86,000 Gas
$ 7.28
~120,000 Gas
$ 10.40
Calculations made with ETH Price of $ 2160.00 and Gas Price of 32 Gwei and bundle size of 20 transactions from activated wallets.


TL;DR You deploy Rule.sol smart contract, which consist of set of rules, that allows Curra to make few actions with your proxy wallets:
  • Deploy Forwarder implementation to your proxy wallets
  • Transfer assets only to your whitelisted wallets, specified at Rule.sol.
Every transaction that violates Rule.sol will simply be rejected by blockchain, that is your main security layer.
It makes Vortex - the first-ever payment processing tool that doesn't require direct access to your assets for processing.
  1. 1.
    You mint Ownership NFT, which is used as a key to deploy Rule.sol.
  2. 2.
    You deploy Rule.sol smart contract with whitelisted destinations (your Omnibus wallets), allowing Curra to deploy specific contracts (Forwarder) and transfer assets solely to your whitelisted addresses.
  3. 3.
    You precalculate address of the proxy wallets with Curra derivation scheme, using CREATE2 algorithm.
  4. 4.
    Curra makes everything work.
You can find detailed explanation here: