Transactions & Mining Rewards (Javascript blockchain, part 3)

This is part 3 of my blog posts series in which we create a blockchain in Javascript. In the previous blog posts we created a simple blockchain and implemented proof-of-work to protect it from spammers and attackers. However we made some shortcuts along the way: our blockchain can only store 1 transaction in a block and there are no rewards for miners. Let’s fix that!

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My second year on YouTube

Exactly 2 years ago I started my YouTube channel and a year ago I published a blog post called "My first year on YouTube" where I wrote about what I had achieved and what my goals were for the upcoming year. So this year I’m doing the same and also adding the goals for my blog & Udemy.

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Static website hosting: who's fastest? AWS, Google, Firebase, Netlify or GitHub?

I've been hosting this website on AWS since 2012 and a lot has changed in the cloud business. So I was wondering if AWS Cloudfront is still the best place to host my static website. What about Google Cloud Storage, Firebase Hosting, Netlify or GitHub Pages? How do they stack up?

Well let's find out!

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Google Sheets as a backend for your applications

A couple of months back I made a Slack bot that allows everyone in the office to place an order for coffee. We have 1 person who is responsible for ordering coffee. He needs to be able to take a look at all the orders that where placed via the Slack bot. That meant that I needed to build a front-end for him as well.

Or maybe not? He used to manage his orders with Excel, so that got me thinking. Google Sheets is just like Excel, but it also has an API that I can access with my chatbot. Could I use Google Sheets as a backend/database for my bot? Well as it turns out...

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Implementing proof-of-work (Javascript blockchain, part 2)

In my previous blog post we created a simple blockchain in Javascript to demonstrate how a blockchain works. However many people commented and said that the implementation wasn't complete and that they could still fool the system. They are correct! Our blockchain needs another mechanism to secure itself against attacks. So let's take a look at how we can do that!

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