How we managed to create a fully functional Blockchain prototype with a new team and no preparation in 7 days

Dawid G.
Published in
7 min readApr 18, 2018

The General Data Protection Regulation (GDPR) is getting more and more attention as the grace period nears its end in late May. Protection of personal data is increasingly important in the EU as data can be used to generate statistics, sell products, and manipulate opinions.

It was against this background that our team was invited to participate in the world’s largest Blockchain Hackathon. Our participation was a last minute dash that was conceived of at the beginning of March. By the time we applied the only way to participate was to jion the Energy Transition Track — not our forte since this is an industry we had little exposure to. We accepted the challenge nonetheless.

Even though we didn’t win first price, we managed to create a fully fledged Proof of Concept. Our prototype uses Hyperleder Fabric, IBM’s permissioned Blockchain that we were introduced to on the day before the Hackathon began. In the aftermath we were invited by two Accelerator Programs from the Energy Sector to present an extended version of our MVP and were listed in the “runners up” group of our track.

tl,dr: our awesome media team compiled a great video telling our story:

This is our story:

During the Blockchaingers Hackathon in April 2018 we were given the unique opportunity to demonstrate our problem solving capability — our target sector was the Energy Transition sector and the challenge was to learn about the newest Blockchain Technologies and come up with a solution in just 3 days. All easy, except we had

  • no solid team (we had 3 people join last-minute)
  • no experience with the new Blockchain Technologies presented
  • no preparation

How could we ensure data privacy in the Energy Transaction business in only 7 days? Can we use Hyperledger Fabric to generate incentives for all parties? Compete with 63 well-oiled teams, who had time to prepare for months?

The Hackathon gave many skilled developer teams the chance to explore new Blockchain technology and solve real world problems offering the finalists 105.000€. With a team of 4 developers, a project manager, a product designer, network specialist and team guide and a personal media team, we accepted the challenge.

The mission: Ensure GDPR compliance in the Energy sector and empower users to own their data

The possible tracks were: Digital Nation Infrastructure, Energy Transition, Global Digital Identity, Health, Machine Economy, Public Safety and Security, The Future of Pensions. We chose the Energy Transition track, which sounded manageable but also challenging.

Energy Providers, Retailers as well as grid owners currently have access to customers energy consumption data (e.g. by gathering it in smart meters) through third party companies who store this data. In the Netherlands its the EDSN. This has many problems:

  • This type of data storage does not comply with the GDPR. How would a contributing party prove GDPR compliance? — How might we offer grid owners a resource friendly and GDPR compliant way?
  • All parties operate within their own interests — So how might we help retain customers, upsell services and ensure GDPR liability?
  • The customers data is completely unprotected
Cryptic ? You bet. These are the four stages of decentralization that await the energy sector in 1st world countries


The hackathon was scheduled to take place on Thursday to Sunday in a little town in the Netherlands called Groningen. It was the second time that DuchChain has invited Blockchain experts from all over the world and started a competition to make the world a better place.

Because most other teams were able to prepare for months in advance (some even brought functional alphas and home built devices), we decided to meet up on Monday, to at least have a few days buffer to sharpen our vision. This ended up being one of the most important things we could do -

(Key Learning #1) Our team felt incredibly empowered to work together after solidifying a vision

We locked ourselves in a nice cabin at a lake in Groningen and used mostly Design Thinking exercises to combine our common knowledge about blockchain technologies and possibilities to define four possible solutions, arranged by their complexity.

On Thursday the organisers of the Hackathon ran hands-on workshops to introduce us to new technologies like Parity or Hyperledger Composer, the latter being a very user friendly interface which allows you to implement and customise a business logic on a blockchain with no deep programming experience.

Friday was the first official day of the Hackathon. This was the first time we heard about the deliverables. We almost forgot that the post-it mess needed to be manifested into something understandable and possibly quantifiable. They called it “The Canvas”

Empty canvas outlining deliverables

Example canvas from the 2017 edition during the captains briefing in the ‘circus venue’ we called it that way because of the nice stage in the background.

This is pretty much what we were working on preparing on Friday. No coding, only concept creation and post-it sticking. This was essential, because diving into code right away would have created too much confusion.

Saturday was the first day of hands-on coding. The concept we created on Friday was still not perfect, because we lacked experience and understanding working with Hyperledger.

(Key Learning #2) We didn’t exactly know what we were capable of so we decided to stop thinking and just started building

This was the moment when we got the ball rolling, because we just started trying to implement our concept, keeping in mind that changes will have to be made along the way. With three talented software developers and two days after the first time we heard about Hyperledger Composer the smart contracts worked and building the front-end was in progress.

With almost no sleep we moved into Sunday, when the Hackathon would end and the all teams had to present their concepts at exactly 12:00.

Our final product / problem canvas (all rights reserved)

Tech Stack

As mentioned above, IBMs permissioned Hyperledger Fabric turned out to be a simple way to describe business logic and implement smart contracts. It was also possible to forward the data to the frontend through NodeJS and display the results from their API. What underscores the simplicity of the Hyperledger design is that we learned of this technology on the day before the hackathon. When it comes to Consortium solution that require permissions, IBM Hyperledger is a serious contender !

The Result

At the end, we didn’t just create a fully working prototype. This was probably the least interesting part. More importantly, we quickly found a way to collaborate as a team and learn more. Everyone came with a skillset and a lot of motivation to change the world and discover something new. With excellent guidance and support from hackathon “Jedi” and IBM consultants we gained a profound understanding of solving global problems, where different parties have different interests and all need to be treated equally.

GDPR compliance is not only a bureaucratic necessity, it also empowers energy consumers and producers with the ownership of their data while unlocking the potential for grid owners and energy retailers to use the data more effectively (for instance through up-selling hardware).

Over the three days we won a lot of fans and even though we didn’t win the first price, we received a lot of interest, met many amazing people and were awarded the “runner’s up” category.

I’m just wondering, if this is something we managed to do with lack of sleep, a team of strangers, no prior knowledge of the technology and no preparation — how much more will we create once we learned the tools and know each others strengths and weaknesses?



Dawid G.

Helping build sustainable economies. ML Engineer and Token Engineer, MSc CS and Intelligent Systems Engineering + BSc Biomedical Engineering @TUHH @Todai