Posts in: Programming

fortune | cowsay

$ brew install fortune $ brew install cowsay $ fortune | cowsay ---------------------------------------- / Retirement means that when someone says | "Have a nice day", you actually have a | shot at it. / ----------------------------------------- ^__^ (oo)------- (__) )/ ||----w | || ||

How to install your SSH key on a remote server

1. Nice way You can install an SSH key by executing ssh-copy-id Now you can log in to the remote server with your password and ssh-copy-id will do the rest. 2. Manual way Append your public ssh key to the authorized_key file on the server. As a one-liner: cat ~/.ssh/ | ssh 'cat>> ~/.ssh/authorized_keys' Conclusion Both commands pretty much do the same. The first way is way easier though.

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Rails: Preview your emails with MailCatcher

Do you know the feeling of copy and pasting the signup-link from this development.log? There’s a better way to do this. For our development environment, we use MailCatcher. MailCatcher runs a super simple SMTP server which catches any message sent to it to display in a web interface. Run MailCatcher, set your favorite app to deliver to smtp:// instead of your default SMTP server, then check out to see the mail that’s arrived so far.

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Host your emails with Mail-in-a-Box

At our cooperative (TechGenossen) we used Gmail as our Email-Provider at first. But we found Gmail to be too expensive for our many members. So, we decided to self-host our emails. Setting up your email server can be quite hard and involves many moving parts. Fortunately, we found Mail-in-a-Box, a fantastic open-source project, which helps you set up a mail server in no time. Mail-in-a-Box lets you become your mail service provider in a few easy steps.

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A short primer on Pair Programming

When I started to pair-programm I had absolutely no idea what I was doing. I sat next to another programmer and we started. Occasionally it worked, but more often it was a frustrating experience. Maybe you are new to pair programming and want to give it a try, or you have trouble getting started. Then this blog post is for you. I show you how we pair at Some of this advice is really obvious — but much of the other stuff we figured out the hard way through pairing over and over again.

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How to manage and share your dotfiles using homesick

Castle 11 from Bill Ward’s Brickpile. (CC BY 2.0) Since quite a while, I try to find a good solution for sharing my dotfiles between my different computers. I started with chef — Unfortunately, this did not work so well. Especially if you also want to use your dotfiles on a server. Also, it felt a little complicated. The next approach I took was putting my dotfiles into my Dropbox and symlink them.

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Script to disable internet connectivity for Mac OS X

From time to time, I really want to make it hard for me to seek for distractions. I found myself using the nice Mac OS X tool Freedom all the time. Freedom disables the network connectivity, which means no Twitter, Facebook etc. But when I revisited the site, I found that the author now charges $10 for it - That’s just a little too expensive in my opinion. So, I went out, and it took me 5 minutes to come up with freedom.

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Lessons from the prime factorization dojo

Last week, my colleagues at, and I had our second Coding Dojo. I learned an important lesson — even though this wasn’t the first time I practiced the kata. The kata The task was to create a class that decomposes natural numbers into its prime factors. Additionally, the factors should be sorted ascending. Examples: 1 => \[] # Since 1 is no prime ;) 5 => \[5] 10 => \[2,5] 75 => \[3,5,5] You get the idea ;)

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