Mini-hackathon with BigchainDB

First of all we want to say thanks to Dimitri De Jonghe from BigchainDB for coming and getting us really excited to work with this great technology!

In the morning, Dimitri started off by explaining the basic principles of BigchainDB, accompanied by some practical use cases. It was a very informative and interactive session.

Let’s start hacking!

After the intro, we brainstormed for some practical use cases to start our small hackathon. We had some discussions and came up with 3 ideas and pitched it to each other.

Team 1: Metamask

This team consisted of: Robbe Van Winkel, Andries Van Humbeeck and Jonas Snellinckx.

The goal of this project was to make something like metamask , but instead of keeping wallets, we were trying to make a standardised identity management plugin which is stored on BigchainDB. Why? So a website can use this plugin to fetch user data instead of the website storing it themselves.

This idea tries to solve the problem of websites needing to be GDPR compliant This tool would help and give the user more privacy by passing the user data through the browser instead of websites storing this data on their servers.

Team 2: Temp-Ted

This team consisted of: Kevin Leyssens, Jeroen De Prest and Vincent Devaux.

The goal of this project was to build a temperature gambling service using Ethereum for the smart contract, BigchainDB for the IoT data stream, NodeJs as the oracilize service and ReactJs for the frontend.

A user can guess the temperature and send an amount of ether with this guess. If he is wrong, he will lose his ether, if he is right, he will get double.

In the backend we pulled the temperature every 5 seconds from 3 sources (yahoo, apix and openweather’s API) and wrote them to our local BigchainDB. So when the temperature is requested, we’ll take the last submitted value of each source and compare them to each other. When 2/3 or 3/3 values are the same, the data is correct, can be trusted and can be seen as a truth. When they are all different, the data is inconsistent and the user will get his money back.

When a guess is submitted from a user, a transaction is send to the Ethereum smart contract with its address, guess and amount of ether. If it is stored successful an event is fired and the right temperature is requested from BigchainDB. We compare it and when it is the same amount as the guess, the ethereum contract will send double ether to the user, if it is incorrect, it will hold the amount.

Team 3: Journels

This team consisted of: Michiel Mulders, Tom Ploem, Senne Theunis.

Our goal was to build a system where each user can add news to the web page and other users can vote for the quality of the article. The content of the article itself should be stored on IPFS, the votes for the article (up / down vote) on BigchainDB.

In the end, we wanted to use a data wallet to allow a user to authenticate through this wallet. This let’s us know who posted an article and what his creditability is (by calculating up / down votes of all his articles).


We all learned a lot of cool and interesting new things during the hackathon. Thanks to the different projects, we had different points of view and usages for BigchainDB. We will definitely use this technology in our future projects, where suited. So start ‘hacking’ with this cool technology!