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an unstoppable exchange for trading Ethereum tokens

The exchange runs entirely on the blockchain, which for clients means: aims to be the leading venue for trading Ethereum assets on-chain, and to help grow an ecosystem of smart contracts trading with each other (and with you).

See in Action

Beta release coming soon …

Demo Screenshot

What can I trade on

Almost anything based on Ethereum (such as ERC20 tokens) can be traded on, either against Ethereum or against other tokens.

This includes coins/tokens connected to organisations in various industries such as:

As well as tokens backed by assets, including:

How does compare to other decentralized exchanges? is the first decentralized exchange to meet the following three tests:

Who’s behind

In one sense, no-one is - the exchange runs entirely on the Ethereum blockchain, and the open source web UI is statically hosted on github (pending move to Swarm). was created by Kieran Elby, a technologist with a background in algorithmic trading systems. He previously spent over a decade building secure, high volume gambling sites for leading bookmakers. He first dabbled in bitcoin in 2013 before flipping to Ethereum in 2015.

The software copyright and other intellectual property is held by Bonnag Limited, a UK registered company.

We’re interested in growing our team in the near future - contact [email protected]

Are there downsides to being 100% on-chain?

Yes - transaction times are much slower than a centralised exchange. This is hard to avoid - 1000s of Ethereum nodes worldwide need to agree on the state of the orderbook (without trusting each other). You won’t find High Frequency Traders on - not necessarily a bad thing for everyone else! We’ve also had to reduce the number of price levels offered to allow us to perform best execution on-chain - so you’ll see prices like 1.23, not 1.2298502.

OK, but how do I withdraw cash from does not interface with the traditional banking system, so if you need cash in your bank account, you’ll need to use a third-party to turn your Ethereum or Ethereum tokens into cash in a bank account.

Over time, we’re confident that withdrawing to cash in a bank account will become less necessary for many clients as:

What are your fees? How do make money?

Because we’re not dealing with banks, or user sign-ups, or hosting providers, we have much lower costs than traditional exchanges.

We guarantee to:

In order to avoid relying on trading fees, we hope to offer value-added products and services that build on top of our core exchange - see roadmap below.

What’s on the roadmap?

Perhaps you have some ideas for smart tokens that can be traded on our exchange, or for autonomous smart contracts that place orders into the exchange - we look forward to seeing what can be done with a fully on-chain trading venue.

Are you planning any sort of ICO / crowdsale?

We are considering using crowd-funding to accelerate our product development (and improve our design and marketing).

We want to make sure we have a working product and a solid business model first though.

Email [email protected] if you’d like to hear about early opportunities to back us.

Give me some technical details!

Take a look at our main smart contract here: BookERC20EthV1.sol.

We’re going to publish full details of how our contracts work as soon as we’ve reached our alpha release.

In the meantime, here’s the original sketch showing the key technique (we call it “price packing”) that allows efficient on-chain best execution matching:

Price Ladder Sketch

I have a question not listed here!

Contact us at [email protected]