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A walk through iExec demo application 2016

Be the first to experience the power of’s distributed cloud

*UPDATE: iExec V3 has been released! and V4 is coming soon!

On May 15th iExec released iExec V3, introducing a new Data Wallet that makes secure data renting possible. V3 upgrades make iExec’s decentralized cloud marketplace faster, more secure and flexible. For the very first time, individuals can connect to iExec and contribute their computing power to earn money. iExec has also launched its Enterprise Edition for corporates wishing to do business with blockchain. ⬇️

OUTDATED (ARCHIVED POST) Welcome to the demo of the iExec blockchain-based cloud. We have created a distributed application (DApp) that you can use to trial our technology today. It’s called VanityGen and is available here.

VanityGen is a Bitcoin vanity address generator that enables the creation of a personalized BTC public address. For example, instead of starting 1XgewroKdN… which is very dull, your address could be 1happyoKdN

Why did iExec develop such a geeky app?

Simply because creating a bespoke Bitcoin address takes a lot of time to compute— but using’s distributed cloud you can send the computation to a network of computers so that it becomes much quicker. This is just one of the benefits of our system and only a tiny part of what can do. What we hope to show is that:

  • The infrastructure to our distributed cloud is ready. Developers could theoretically now schedule tasks for to execute — API coming soon!
  • One can develop DApps that harness’s superior computing power. The system’s native RLC token can be used to access off-chain computing resources.

The VanityGen DApp relies on XtremWeb-HEP, an open source software that’s been developed by Oleg Lodygensky and Gilles Fedak. You can actually see what happened on workers’ side (‘miners’ or ‘servers’). The vanitygen software is the open-source version hosted on Github. To learn more about technical aspects of, you can read this series of articles describing the infrastructure in detail.

How to use the demo app?

Step 0

If you don’t have Metamask installed (Ethereum wallet), you can download and add Metamask Chrome extension. Of course, you don’t need it if you already have an Ethereum node running.

Make sure that “Ropsten Test Net” (Metamask window top left icon).

Before you can spend your RLC testnet token, you want your account to be credited: just click on the ‘Get RLC’ button, a Metamask window will appear so you can sign this transaction by clicking the “Accept” button.

You can check your balance using Mist web interface. Click on “Contracts”, then “Add a token” and copy-paste the unique contract address :


In the “token contract address field”, the other fields will be automatically filled.

Congrats! You now own 5 RLC testnet token and you’re ready to use one to run the app. If you’re in a greedy mood, you can repeat this operation as many times you want.

Step 1 is one of the oldest Bitcoin address generators. As you might know, a Bitcoin private key is your account security and must never be reveal so Bitcoin keys pairs must be generated by you and only you. That’s why you’ll need to copy and paste a few strings. This can’t be done automatically.

Follow the instructions closely then click on the “Next” button.

Step 2

Paste your Bitaddress generated public key and choose the letters you want to see at the beginning of your Bitcoin address (all Bitcoin addresses start with a “1” and you don’t need to add it in this field), then click on “Launch Job”.

NOTE: A ‘job’ is a technical terms that refers to the task you’re sending to the swarm of server providers that will calculate the pool part-private key.

A link to XtremWeb-HEP interface will appear, you can click on it to get more info about the job you just launched.

When the “Next” button becomes active, click on it.

Step 3

Click on the “Get Result” button and copy the “privkeypart”. Then go back to and paste it in the “Enter Pool Part Private Key” field. You also need to copy-paste the part-private key that was generated on bitaddress.

Click on “calculate” to get your vanity address public and private key. Make sure you safely store your private key.

You can use this QR code generator to import your private key to your favorite wallet and enjoy your brand new Bitcoin vanity address!

If you meet some difficulties, feel very free to ask your questions on our Slack or send us an email at

Thanks for reading.



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