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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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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Buying and trading cryptocurrencies is all the rage right now. But how do you actually keep track of your investments? Especially if you do them on various websites. There are a few websites out there that allow you to do this, but most of them are rather complex.

Instead I made a simple spreadsheet in Google Drive and added a little Google Script magic to it so that it automatically updates my losses/profits. Let's take a look at how it works!

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Almost everyone has heard about cryptocurrencies like Bitcoin and Ethereum, but few people actually know how the technology behind these work. In this blog post I'll create a simple blockchain in JavaScript to demonstrate how they work internally. I'll call it SavjeeCoin!

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Last year I wrote a blog post about how to use LXC containers on a VPS. I've been running this setup for quite a while now and it has been great. However, my approach involved making full copies of my containers. Not very space or cost efficient!

So it was time to revisit my backup strategy: I started using Duplicity to take incremental and encrypted backups of my LXC containers. I also switched from Amazon S3 to BackBlaze B2 to further reduce my storage costs.

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