hack & travel

How I trained sheet reading using the Web MIDI API

July 07, 2015 • hack

I built a web app to train sheet reading skills with a real piano. The web app renders random music sheets and the user has to play the notes on his piano. The communication between piano and browser is implemented with the help of the Web MIDI API.

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The case for containers

June 27, 2015 • hack

This week all major industry players joined forces to come up with a common standard format for Linux containers. This is great news because imho containers will play a major role in deployments. They are the key enabler of the DevOps methodology and will drive IT efficiency improvements in many organizations.

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Intention analysis using topic models

February 14, 2015 • hack

Topic models are great to categorize WHAT a text is about. It is pretty easy as well: Get an off-the-shelf LDA, train it on your corpus and you are set to go. But there are even more insights you can get about your texts. Modifying your corpus in a certain way (mostly removing everything but verb phrases) allows you to gather a deeper understanding about WHY a certain text was written.

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Invoice compiler

October 05, 2014 • hack

Writing invoices to clients has been one of the more annoying tasks in our monthly routine. Our invoice compiler now automates a large portion of that.

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Pimping Backbone with Marionette

September 21, 2014 • hack

Backbone offers guidance but leaves us the freedom to only extend the parts we really need. However, this minimalistic approach sometimes leaves a few things to be desired. Marionette helps here and provides a library that supplements vanilla Backbone very nicely by implementing best practices and common patterns.

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Salt-Event-Hub - Saltstack in RESTful way

August 18, 2014 • hack

Salt is an integral part of our infrastructure. Harnessing its full power is possible by utilizing the salt event system. Unfortunately, events can currently only be triggered through so-called minions which have to accompany the service that interacts with the salt event system. Since this is not always the case, we created the salt-event-hub: A simple RESTful HTTP server that would allow us to use a widely supported interface to interact with our infrastructure.

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Why gulp might not be the answer.

July 25, 2014 • hack

In the course of time a lot of frontend build systems have emerged and raised hopes to be the ultimate solution. Gulp, Broccoli and Metalsmith are only some of the contenders. This post compares these tools including their advantages and disadvantages.

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Customizing CoffeeScript

July 10, 2014 • hack

We have build some fairly large single-page apps and chose RequireJS as a module / dependency system to keep our code organized and not go crazy. Unfortunately, the model definition syntax has a few disadvantages. We fixed this by customizing the CoffeeScript compiler and creating a simpler syntax.

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June 13, 2014 • hack

The Time-Tracker helps teams and individual developers to log the time they spent working on specific GitHub issues. It is designed to integrate seamlessly into your development process, by hooking directly into GitHub issues. You and your team have the ability to log your working hours and keep track of your monthly progress.

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Managing fine-grained mongoDB object access in Scala

November 04, 2013 • hack

Restricting db access to certain collections or even specific objects is a major requirement for a lot of software projects. Here is how we satisfied this requirement with fine grained access control on a per object basis.

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