Integration Overview

This documentation is also available as a PDF.

Dash Core is a “fork” of Bitcoin Core and shares many common functionalities. Key differences relate to existing JSON-RPC commands which have been customized to support unique functionalities such as InstantSend.

  1. General Information: Dash is a “Proof of Work” network and is similar to Bitcoin.
    1. Block Time: ~2.6 Minutes per Block
    2. Github Source: https://github.com/dashpay/dash
    3. Latest Release: https://github.com/dashpay/dash/releases
  2. JSON-RPC Interface: The majority of commands are unchanged from Bitcoin making integration into existing systems relatively straightforward. Note that the following commands have been modified to support InstantSend:
  3. Block Hashing Algorithm: Dash uses the “X11” algorithm in place of SHA256 used in Bitcoin. It’s important to note, however, that this only affects the hashing of the Block itself. All other internals utilize SHA256 hashes (transactions, merkle root, etc) which allows for most existing libraries to work in the Dash ecosystem.
  4. Special Transactions: Dash Core v0.13.x introduces the concept of “Special Transactions”. Please see the Transaction Type Integration Guide for more information.

Special Transactions

This documentation is also available as a PDF.

Dash 0.13.0 and higher implement DIP002 Special Transactions, which form a basis for new transaction types that provide on-chain metadata to assist various consensus mechanisms. The following special transaction types exist:

Release Version Type Payload Size Payload Payload JSON Transaction Purpose
v0.13.0 3 0 n/a n/a n/a Standard Transaction
v0.13.0 3 1 <variable int> <hex> proRegTx Masternode Registration
v0.13.0 3 2 <variable int> <hex> proUpServTx Update Masternode Service
v0.13.0 3 3 <variable int> <hex> proUpRegTx Update Masternode Operator
v0.13.0 3 4 <variable int> <hex> proUpRevTx Masternode Revocation
v0.13.0 3 5 <variable int> <hex> cbTx Masternode List Merkle Proof
v0.13.0 3 6 <variable int> <hex> qcTx Quorum Commitment

Integration notes:

  1. DIP002 Special Transactions are a foundational component of Dash Core v0.13.0 and introduce a new Transaction Version and related “Payload” to the network.
  2. Integrated Systems must be able to serialize and deserialize these new Transaction Types in order to accurately encode and decode Raw Transaction data.
  3. From a backwards compatibility perspective, the 4 byte (32-bit) version field included in Legacy Transactions has been split into two fields: version and type (each consisting of 2 bytes).
  4. Refer to the Special Transactions section of the dash developer reference for additional detail on these data types, e.g. <variable int>.
  5. InstantSend status and Payload JSON (e.g. proRegTx) is included in the JSON-RPC response, please note that this data is not part of the calculated hash and is provided for convenience.

See the v0.13.0 transaction types integration documentation (PDF) for worked examples of each transaction type.

InstantSend

This documentation is also available as a PDF.

InstantSend is a feature provided by the Dash network that allows for zero-confirmation transactions to be safely accepted and re-spent. The network attempts to lock the inputs of every valid transaction when it is broadcast to the network. Every secured transaction is included in a following block in accordance with standard blockchain principles.

InstantSend is enabled by the Masternode Network which comprises approximately 5,000 masternode servers. These nodes are differentiated from standard nodes by having proven ownership of 1,000 Dash, making the network highly resistant to Sybil attacks. Masternodes form Long-Living Masternode Quorums (LLMQs), which are responsible for providing near instant certainty to the transaction participants that the transaction inputs cannot be respent, and that the transaction will be included in a following block instead of a conflicting transaction.

This concept works as an extension to Nakamoto Consensus. InstantSend enables transacted funds to be immediately and securely respent by the recipient, even before the transaction is included in a block.

Receiving InstantSend Transactions

Receiving an InstantSend Transaction introduces two requirements:

  1. The ability to determine the “InstantSend Status” of a given transaction.
  2. The ability to adjust “Confirmation Status” independently of block confirmation.

InstantSend Status is typically determined through direct connection with the dash daemon, ZMQ notification, or through the usage of an external wallet notification script.

Direct Connection: InstantSend Status can be identified through direct connection with the Dash daemon using JSON-RPC protocol. The “instantlock” attribute of the JSON response reflects the status of the transaction and is included in the following commands:

ZMQ Notification: Whenever a transaction enters the mempool and whenever a transaction is locked in the mempool, ZMQ notifications can be broadcast by the node. A list of possible ZMQ notifications can be found here.

The following notifications are relevant for recognizing transactions and their corresponding instantlocks:

  • zmqpubhashtx
  • zmqpubhashtxlock
  • zmqpubrawtx
  • zmqpubrawtxlock

Wallet Notification: The Dash Core Daemon can be configured to execute an external script whenever an InstantSend transaction relating to that wallet is observed. This is configured by adding the following line to the dash.conf file:

instantsendnotify=/path/to/concurrent/safe/handler %s

This is typically used with a wallet that has been populated with watch-only addresses.

Broadcasting InstantSend Transactions

Since Dash v0.14.0 established LLMQs on the Dash network, quorums will now attempt to lock every valid transaction by default without any additional fee or action by the sending wallet or user. A transaction is eligible for InstantSend when each of its inputs is considered confirmed. This is the case when at least one of the following circumstances is true:

  • the previous transaction referred to by the input is confirmed with 6 blocks
  • the previous transaction is confirmed through an older InstantSend lock
  • the block containing the previous transaction is ChainLocked

When checking the previous transaction for an InstantSend lock, it is important to also do this on mempool (non-mined) transactions. This allows chained InstantSend locking.

Additional Resources

The following resources provide additional information about InstantSend and are intended to help provide a more complete understanding of the underlying technologies.

API Services

This documentation is also available as a PDF.

Several API services exist to facilitate quick and easy integration with the Dash network for services including:

  • Transaction broadcasting
  • Exchange rates
  • Currency conversion
  • Invoice generation

API Services are typically leveraged to eliminate that requirement of running your own infrastructure to support blockchain interactions. This includes mechanisms such as:

  • Forming and Broadcasting a Transaction to the network.
  • Address generation using HD Wallets.
  • Payment Processing using WebHooks.

There are a variety of options for supporting these methods, with the key differentiator being the pricing model included and supported features. The following list of API Providers attempts to outline these key features/differentiators and also includes a link to related documentation.

Insight

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https://github.com/dashevo/insight-api

The open-source Insight REST API provides you with a convenient, powerful and simple way to read data from the Dash network and build your own services with it. A practical guide to getting started with the Insight API and Insight UI block explorer is available here.

BlockCypher

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https://www.blockcypher.com

BlockCypher is a simple, mostly RESTful JSON API for interacting with blockchains, accessed over HTTP or HTTPS from the api.blockcypher.com domain.

BitGo

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https://www.bitgo.com

BitGo provides a simple and robust RESTful API and client SDK to integrate digital currency wallets with your application. Support for Dash InstantSend is available.

  • Features: Multi-Signature HD Wallets, Wallet Operations, WebSocket and WebHook Notifications, Custody Solutions
  • Pricing Model: Per API Call
  • Documentation: https://www.bitgo.com/api/v2/

ChainRider

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https://www.chainrider.io

ChainRider is a cloud service providing a set of REST APIs for digital currency management and exploration.

  • Features: Blockchain queries, Event Notifications, Transaction Broadcast, Payment Processing, etc.
  • Pricing Model: Free trial, pay per API call
  • Documentation: https://www.chainrider.io/docs/dash

GoCoin

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https://gocoin.com

The GoCoin platform makes taking Dash as easy as installing a plugin. Payment processing is already implemented for every major shopping platform. GoCoin is focused on helping merchants in privacy-related niches and specific industries, and handles all transaction risk for all payments from your customers.

  • Features: Invoicing, Exchange Rates, WebHook Callbacks. GoCoin holds Private Keys on their server allowing the merchant to withdraw funds in Cryptocurrency or convert to Fiat.
  • Integrations: WooCommerce, Magento, Prestashop, VirtueMart, ZenCart, OpenCart, OSCommerce, UberCart, nopCommerce, WHMCS, NATS4, Shopify.
  • Pricing Model: 1% Processing Fee (https://gocoin.com/fees)
  • Documentation: https://gocoin.com/docs

CoinPayments

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https://www.coinpayments.net

CoinPayments is an integrated payment gateway for cryptocurrencies such as Dash. Shopping cart plugins are available for all popular webcarts used today. CoinPayments can help you set up a new checkout, or integrate with your pre-existing checkout.

  • Features: Invoicing, Exchange Rates, WebHook Callbacks. CoinPayments holds Private Keys on their server allowing merchant to withdraw funds in Cryptocurrency or convert to Fiat.
  • Integrations: aMember Pro, Arastta, Blesta, BoxBilling, Drupal, Ecwid, Hikashop, Magento, OpenCart, OSCommerce, PrestaShop, Tomato Cart, WooCommerce, Ubercart, XCart, ZenCart
  • Pricing Model: 0.5% Processing Fee (https://www.coinpayments.net/help-fees)
  • Documentation: https://www.coinpayments.net/apidoc

SDK Resources

This documentation is also available as a PDF.

SDKs (Software Development Kits) are used to accelerate the design and development of a product for the Dash Network. These resources can either be used to interface with an API provider or for the creation of standalone applications by forming transactions and/or performing various wallet functions.

Dash Developer Guide

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https://dash-docs.github.io/en/developer-guide

The Dash Developer Guide aims to provide the information you need to understand Dash and start building Dash-based applications. To make the best use of this documentation, you may want to install the current version of Dash Core, either from source or from a pre-compiled executable.

NodeJS/JavaScript: Dashcore

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https://bitcore.io

Dashcore is a fork of Bitcore and operates as a full Dash node — your apps run directly on the peer-to-peer network. For wallet application development, additional indexes have been added into Dash for querying address balances, transaction history, and unspent outputs.

PHP: Bitcoin-PHP

https://github.com/snogcel/bitcoin-php

Bitcoin-PHP is an implementation of Bitcoin with support for Dash using mostly pure PHP.

Python: PyCoin

https://github.com/DeltaEngine/pycoin

PyCoin is an implementation of a bunch of utility routines that may be useful when dealing with Bitcoin and Dash. It has been tested with Python 2.7, 3.6 and 3.7.

Java: DashJ

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https://github.com/HashEngineering/dashj

DashJ is a library for working with the Dash protocol. It can maintain a wallet, send/receive transactions (including InstantSend) without needing a local copy of Dash Core, and has many other advanced features. It’s implemented in Java but can be used from any JVM compatible language: examples in Python and JavaScript are included.

Objective-C: Dash-Sync

../_images/dash-logo.png

https://github.com/dashevo/dashsync-iOS

Dash-Sync is an Objective-C Dash blockchain framework for iOS. It implements all most relevant Bitcoin Improvement Proposals (BIPs) and Dash Improvement Proposals (DIPs).

.NET: NBitcoin

../_images/dash-logo.png

https://github.com/MetacoSA/NBitcoin

NBitcoin is the most complete Bitcoin library for the .NET platform, and has been patched to include support for Dash. It implements all most relevant Bitcoin Improvement Proposals (BIPs) and Dash Improvement Proposals (DIPs). It also provides low level access to Dash primitives so you can easily build your application on top of it.

BlockCypher

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https://www.blockcypher.com

BlockCypher also offers client SDKs.

GoCoin

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https://gocoin.com

Vending Machines

Community member moocowmoo has released code to help merchants build their own vending machine and set it up to receive Dash InstantSend payments. The Dashvend software can also be used to create any sort of payment system, including point-of-sale systems, that can accept InstantSend payments.

Price Tickers

You can add a simple price ticker widget to your website using the simple code snippet generator from CoinGecko.

Similar widgets with different designs are available from CoinLibWorldCoinIndex and Cryptonator, while an API providing similar information is available from DashCentral.

QR Codes

Many wallets are capable of generating QR codes which can be scanned to simplify entry of the Dash address. Printing these codes or posting the on your website makes it easy to receive payment and tips in Dash, both online and offline.

  • In Dash Core, go to the Receive tab, generate an address if necessary, and double-click it to display a QR code. Right click on the QR code and select Save Image to save a PNG file.
  • In Dash for Android, tap Request Coins and then tap the QR code to display a larger image. You can screenshot this to save an image.
  • In Dash for iOS, swipe to the left to display the Receive Dash screen. A QR code and address will appear. You can screenshot this to save an image.
  • To generate a QR code from any Dash address, visit CWA QR Code Generator and simply paste your Dash address to generate an image.