CYPRA

SEND, SPEND & EXCHANGE CRYPTO ASSETS INSTANTLY WITH NO INTERMEDIARIES AT THE LOWEST COST

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Privacy first
non-custodial SPV wallet with client-side BIP-158 filters .
Atomic swapping
p2p atomic swaps for currencies.
Multicurrency
BTC, ERGO, USDT.
Coinjoin
p2p coin mixing service integrated inside the wallet.
Multiplatform
desktop and mobile.
Decentralized
deploy full node and start making money with us.
Minimalistic
lightweight, simple and convenient.
Opensource
sources are open for usage and security analysis.

In details

Indexers are a crucial part of the project.

Their first task is to track several cryptocurrencies and prepare filters for each of them. More on filters in the SPV section.

Indexers form a decentralized network for our blockchain. It hosts and manages orders for atomic swaps.

We host a number of indexers as a backbone of the network. Their URLs are hard-coded into the app and they serve as a bootstrap.

Indexers are open-sourced as well, so you can set up your own indexer, join the network, and start mining tokens!

Tokens are used to pay fees for placing exchange orders in the blockchain, so you will most likely need them.

However, decentralization does not stop there! The app allows you to create an exchange order and send it manually to a friend, who will paste it into his or her app and perform the swap. No fees, no information stored in the blockchain. A perfect solution for an extra cautious user.

SPV stands for Simplified Payment Verification.

The app downloads filters for your cryptocurrencies from indexers and stores them. Filters follow BIP-158.

After syncing the storage will have one filter per block. Given an address and a filter the app checks if the corresponding block contains transactions relevant for the address. If it does, then the block can be requested directly from the blockchain's node. You don't need to store the entire chain to keep track of your balance.

To ensure privacy, the app downloads filters for the whole chain. This way indexers don't know which addresses you are interested in. However, this means that the app will have to download a lot of data after the initial setup. Filters for Bitcoin's chain take up about 150MB. This data is shared among all wallets on the device.

Atomic swaps allow you to exchange cryptocurrencies without relying on a third party. Two parties post smart-contracts to respective chains to initiate the exchange.

In the next stage, if one party fails to transfer funds, the other can cancel the exchange and pull its money back.

It is widely known that Bitcoin provides only pseudo-anonymity that allowes third parties to track history of coins and derive identity information. It is enough to pass KYC checks in some point of your financial history to deanonymize all your future transactions. So, we provide a built in P2P service for beating this issue called CoinJoin

Consider Alice wants to pay Ted and Bob wants to pay Mike. Two transactions are created in typical scenario that allows to track backward who pays whom.

Instead, Cypra wallet merges transactions into single one. It becomes impossible to track back who actually pays Ted and Mike.