In this first level we need to try and become the owner of the contract in order to be able to draw funds from it. After inspecting the contract we can see that there is a contribute() methods, which allows us to become the owner if we contribute more than the original owner of the contract. function contribute() public payable { require(msg.value < 0.001 ether); contributions[msg.sender] += msg.value; if(contributions[msg.sender] > contributions[owner]) { owner = msg.sender; } } In the constructor we can see that the original owner has put 1000 …

Openzeppelin is well-known for their battle-tested contracts we can build upon in order to create our own ERC-20 or ERC-721 tokens and more. What they also provide is an excellent security game that teaches your the basics of smart contract security. There is no shortage of hacks resulting in millions of dollars of losses caused by insecure smart contracts. As developers, there's always something we can learn and I found the Ethernaut game to be an excellent introduction for anyone getting started with smart contract development in Solidity. I've written down my own process and …

I recently dove into the rabbit hole of blockchain development on Ethereum and love it! This article assumes that you are developing contracts in the hardhat framework. Verifying contracts on Etherscan Verifying and uploading contracts directly on Etherscan is easy enough, especially when you are coding up a simple one-file contract in remix . When you have just one file, it's a matter of simply uploading your compiled code and you're good to go. Once you start developing more complex contracts that use dependencies like the openzeppelin contracts you'll notice that you …

First of all, I hope you are all doing well and your families are healthy. The worldwide Corona pandemic has taken the world by surprise and lockdowns in all shapes or forms have put an abrupt end to the lives we typically live.  That means many of us are working from home now and are probably hopping from conference call to conference call like this guy . Before the Corona outbreak I would normally teach in college and work with my students in person on a daily basis. While I'm writing this, all schools are closed and lessons have moved to online platforms. Luckily I had previousl…

My friends know me as someone who is somewhat of a privacy nerd. Whenever they can, they'll tease me about my views on privacy and will tell me that when you have nothing to hide you have nothing to fear . I disagree.  Earlier this week my friends asked me what I thought about the Belgian government wanting to put our fingerprints on our national passports. They don't see a problem with that because they have nothing to hide or so they claim. If the fingerprints help catch a couple of criminals, that must a good thing, right?  I don't know how far people are willing to go but why …

Inspired by all the interesting pages over at Wes Bos'  https://uses.tech  — here's some of the gear and tools I use daily. Hardware Macbook pro — for teaching AOC U2777PQU monitor — plugged in to my Macbook pro iMac 27 inch — daily work Evoluent verticalmouse 4 — great mouse, especially if you are prone to RSI Devine PRO-USB1 USB microphone — for recording video courses Twelve South hi-rise stand Raspberry pi — device of choice for hacking and network intrusion ECM Botticelli II — for ☕️ Software Design …

In the past few months I've become increasingly more interested in online security and hacking. In school — where teach web development and server management — I like to educate myself and my students about online risks and techniques hackers are using against our web apps and servers. By knowing how our apps can be attacked and exploited we can all be better informed and aware of the risks that arise when building and deploying apps. I believe the best way to learn anything is by doing. That's why I decided to try and hack my own students during our weekly labs. Every week I studied a …

Good news for all web developers who want to learn Docker or the fantastic Laravel PHP framework. I've recently launched a new micro-platform over at https://courses.goodbytes.be where I'll be adding new video courses on a regular basis. Courses are all in Dutch so only Dutch-speaking developers need to apply at this point in time. What courses are available? Responsive web design If you are new to web design and quickly want to learn how to build a responsive website, we'll dive deep into HTML ans CSS to get that done. This courses is the same one we use in my web design …

[if you are just looking for a quick way to get a LAMP-stack running in docker without needing any explanation, check out this repository ] Getting started with docker can be daunting at first, just like getting started with any technology you're not yet familiar with. Remember your first steps with vagrant, node, npm, mongodb, sass, js ... or any other tool/technology you thought you didn't need? You'll feel the same about docker. Let me save you some time and explain the basic concepts to get you started as quickly as possible. Heads up : I'm recording a free 1-hour …

I'm currently in the process of releasing a tool I've been using myself for some time. The tool is called BuzzApp.rocks  is geared towards online marketeers. Chances are you are looking for a marketing channel that has a high conversion rate and that is easy to manage. Web push notifications are what you are looking for. BuzzApp itself is a marketing automation tool that you can use to easily schedule automated web push notification campaigns. Just think of it as MailChimp, but for web push campaigns. The web is catching up with native mobile apps rather quickly and today you can …