CodeBlock: A Blockchain Developer Day from Blockchain


Eight awesome blockchain presentations across a wide range of topics.

One hundred crypto nerds.

A perfectly organised event.

All made for an inspiring Saturday down at Campus London.

First, I would like to say thank you to Blockchain the company for organising the event.

I didn’t know what to expect from the day. When I first found out the name of the company — Blockchain, I thought it rather odd. But these guys are the real deal. Formed in 2011, they were Blockchain before blockchain was blockchain. How cool is that?

The day was jam packed with information. Each talk provided new knowledge and insights to digest. New questions to ponder. And new tools/projects to check out.

Each talk presented me with new threads of the blockchain puzzle to try to unravel.

I learnt a lot!

The History of Block Chain Technology

By Nic Cary, the co-founder of Blockchain. The company which organised this event.

It was a great start to the day. Looking back at the history of the blockchain space. Through the inception of Bitcoin, the pizza transaction, the creation of Blockchain the company and a lot more.

I particularly enjoyed this funny video of early bitcoin adopters destroying their iPhone’s. All because Apple kept removing bitcoin wallets from their app store.

Anatomy of a Bitcoin Transaction

A talk by Sjors Provoost. A true bitcoiner who has recently started contributing to Bitcoin core.

Sjors clearly has a wealth of knowledge about Bitcoin. His talk provided a deep dive into Bitcoin’s utxo transaction model. Including a look at some opcode for how a Bitcoin transaction occurs.

He also provided a new perspective on why it’s a good thing Bitcoin mining requires dedicated hardware which went something like this.

If the hardware required to secure the network was just general CPU power. Organisations might already have a meaningful amount of compute power compared to the total power of the network. Therefore they may be capable of attacking the network should they decide to do so.

Think NSA, GCHQ or even Google.

The expensive cost of buying new dedicated hardware makes this far less likely to happen.

A very good argument and not one I had considered before.

I enjoyed chatting with Sjors over a beer. We discussed upgrading Bitcoin and why this is a slow process. OP_NOP, the opcode that does nothing in Bitcoin yet but could potentially be used to add new functionality.

He also spoke of his interest in Simplicity. A new language for blockchains designed by Blockstream. One a bit more thought out than the current opcodes implemented in Bitcoin and Ethereum. Simplicity was one of many things I took away from this day to look into further from this day.

Towards a Generalised Block Chain Fabric

By Imperial College London PhD student Alexei Zamyatin.

This was the talk that stood out to me when looking first at the schedule.

It did not disappoint.

Atomic cross-chain swaps, chain relays and Meta-layer protocols made for a very technical presentation. While it was a real head-scratcher at times, Alexei presented a clear picture of a very complex topic.

I was thoroughly impressed with his presentation.

I find the question:

How can we enable secure communication and transfer of value between different blockchains?

really interesting and technically challenging. But also vitally important. It is going to be exciting to watch the progress in this area over the next few years.

I enjoyed the section about Polkadot. A heterogeneous multi‑chain technology being developed by Parity. I hope to read the Polkadot white paper over the next few days. Another one of those threads to unravel.

It looks complicated because it is.

Alexei also made an interesting comment about the alarming shift to centralised solutions. Often these cross chain solutions begin with a set of predetermined validators. They claim they will shift towards a more decentralised model in the future. But as Alexei pointed out, what is the incentive to shift to a decentralised model after the system has been created?

Having centralised systems makes things easier, faster and more efficient. Will these projects really shift towards a more decentralised model in the future?

I guess we will have to see.

Application of Blockchain APIs

By Justin Tormey a developer at Blockchain.

This talk gave an insight into what Blockchain the company does and why it is so useful.

Blockchain are building the infrastructure for Bitcoin. Their main product is an online crytocurrency wallet — mainly for bitcoin. However, the most interesting product for me are the API’s they are developing.

This was the premise of Justin’s talk.

The API’s allow users to query and interact with the Bitcoin blockchain. You can subscribe to incoming transactions, send transactions and a whole lot more.

Justin gave a live coding demo of these API’s being used with a great use case. He developed a simple program to listen for incoming transactions arriving at his bitcoin address. Once a transaction appeared on the network the program then checked his new balance. If it was above a certain amount the code sent a transaction with the majority of the funds to a cold wallet.

This provides a solution to the problem I am sure a lot of people have with online wallets. Security.

Fascinating stuff. Check out the API’s provided by Blockchain here.

Crypto Markets and the Future of Digital Assets

By Xen Baynham-Herd. The Head of Strategy & Lead Economist at Blockchain.

Xen’s talk provided a tantalising vision of the future as more and more of our assets become digitised.

He described a cryptopia …

A future where you automatically stream money to a self-driving car for the time of your journey. This car is then able to pay other cars for priority depending on journey requirements.

A future where you can send money instantly to charities anywhere in the world in response to a natural disaster.

A future where content providers get streamed money for the amount of time someone spends digesting their content.

A future where the exchange of value is frictionless and accessible to all.

I loved it.

“Our vision is not restricted to making the existing financial system marginally more efficient. We have the opportunity to build an entirely new one” — Xen

Both images are taken from Xen’s slides — I hope he doesn’t mind.

An Introduction to Smart Contracts

By Dominik Harz, Research Assistant at the IC3RE.

Dominik clearly knew his stuff when it came to smart contract development. He explained Ethereum, smart contracts and smart contract security. Finishing with a look into some of his current research.

Dominik also gave a simple, but incredibly useful, demo. Deployed a simple voting smart contract to a test net and interacting with it once deployed.

I am currently trying to learn as much as possible about smart contract development. Deploying and testing them has always been a challenge for me. I picked up a lot of tips and tools from watching Dominik.

For one, use truffle develop, an interactive console which spawns a new development blockchain. I am also going to look into Ganache cli, a fast Ethereum RPC client for testing and development.

Seeing Ganache work provided a solution to an issue I had been running into when testing smart contracts through remix. I only ever was able to test with one address, this reduced my testing capabilities. With Ganache you can assign multiple addresses in the test network.

Both Dominik and Alexei are lucky enough to have their research sponsored by Blockchain. I didn’t particularly enjoy university but studying this technology full time sounds awesome. I couldn’t help being a little jealous.

Ethereum: Past and Present

By Vinay Gupta. A cypherpunk, founder of mattereum and veteran of the blockchain space.

Wow, this talk was awesome!

Before this event I had never heard of Vinay Gupta. After I left I had a clear sense that Vinay was one of the leading thinkers in this new field.

Vinay spoke clarity, experience, and understanding of the whole space. As well as having thought about its implications on the wider world. A world which distributed ledger technology must try integrate with.

His company mattereum, with the tag line *Smart contracts for the real world, *are trying to do just that.

I loved his comparison between technology and magic. Society doesn’t care how things work as long as they work. So for all intense and purposes it’s magic.

The problem is the cryptography underpinning this space is not quite at the stage where people have accepted it and just agree that it works.

Vinay gave a reality check to the current blockchain enthusiasm. Posing an interesting question:

Is blockchain going to turn into a sealed box that does something specialised but outside it’s field has very little impact?

Like edi, a hyped technology back in the day. Most of us had never heard of it. Proving his point.

Or could it become like HTTPS. Which gets used every day by everyone without anyone paying it much notice or caring how it works.

He then went on to point that actually blockchain was trying to become much more. Where HTTPS integrated an existing payment system into the internet with minimal lines of code. Blockchain technology is trying to build a new payment system from scratch. Potentially a new internet along with it.

Is that really going to work?

I think Vinay believes in this technology, he is working really hard to make it work. However he seems more aware of the challenge than most people. I got the sense that he has been here before.

Another interesting analogy Vinay gave for the blockchain was of it being exploited. Imagine the USA running it’s black ops on Zcash or some other uber private coin. Is that really a good thing?

Are we protecting weak from strong or strong from weak? — Vinay Gupta

All of that was just the introduction.

Vinay went on to explore digital identity in depth. A topic I have recently been grappling with myself. A crucial, yet unfathomably difficult problem we need to solve in order to bring about the future blockchain promises.

He emphasised the importance of solving key semantics. Mentioning SDSI and SPKI. These are public certificate mechanisms (I need to look into these further). And talked in depth about identity, a subset of key semantics.

His thoughts on identity insurance presented a well thought out solution to one of the problems of digital identity. How do I know the information when verified and claimed against on the blockchain was legit? What if the passport was fake?

Once information in the blockchain it’s almost certainly going to be believe whether true or false. How do we protect against this risk?

Vinay’s elegant solution — Insurance. Much like VISA has insurance for transaction fraud, the identity solution of tomorrow could have insurance against identity fraud.

Vinay’s key message:

Could not have put it better!

I wish we had asked Vinay more questions. I should of asked him a question. I think my brain was still trying to process all the information gathered throughout the talk.

If I could ask a question now it would be something like:

Explain key semantics in a sentence?

Although I can think of plenty. Vinay is definitely a fountain of knowledge in the digital identity field.

Anyone else interested in digital identity should definitely check out this talk by Vinay. Also look into The Internet of Agreements. They are hosting an identity conference April 10th which I am looking forward to attending.

Off-Chain Payments for Fun and Profit, Liquidity.Network and REVIVE

By Arthur Gervais, lecturer at Imperial College London.

This was another interesting one. They were all interesting!

Arthur gave an explanation of payment channels — he covered a full range. Uni-directional and Bi-directional payment channels. 2 party and n party payment hubs.

N-party payment hubs is the solution that Liquidity.Network provides. A company that Arthur is co-founder of. These payment hubs bring some real benefits such as low maintenance costs, low setup costs and high user throughput.

The basic idea is that instead of having to put a stake down for each payment channel you open, you can just single stake for your payment hub.

It sounds like a really exciting project. The talk included a live demo of the wallet in action deployed on an ethereum test network. You can test it for yourself here.

Arthur has also developed an open source bitcoin simulator and lectures on blockchain at ICL. Check out his course slides here if you’re interested.

The Community

Dispersed throughout the day was a refreshments. They put on a really good spread. Breakfast, coffee, lunch and even beers afterwards.

This time was perfect for learning from the community. Sharing knowledge, discussing the talks and hearing about interesting projects.

Everyone was friendly. There was a real sense of excitement at this event, a sense that you are part of something important. On the cutting edge.

One of the projects that I heard about through community discussion was Zap wallet. An open source, user focused lightning wallet for bitcoin. I met Diogo Sergio, who is currently helping with the UI/UX for this project. Pretty cool stuff.

Thank You

This event exceeded my expectations, well worth the journey down from Leeds. The range of topics covered, the quality of the talks, the discussions, the community. You can view all the slides presented throughout the day here.

I left saturated with new knowledge and excited about the new areas I had discovered to explore.

Thanks to my sister for putting me up for the weekend.

Me too!

Thank you Blockchain for organising such an epic event!

I hope to be back for more soon.

Thanks for reading

If you have any questions, feel free to drop me an email.