Babbel Bytes

Insights from the Babbel engineering team

Evolution of Babbel’s data pipeline on AWS: from SQS to Kinesis

Kirill Shirinkin

Various data storages have seen increased growth over the last few years. There are now so many of them that it becomes overwhelming to choose the right tool for the job. Among all of the Big Data ready replacements for traditional relational databases (think Cassandra or HBase), there are also a few tools that try to solve a slightly different problem: to provide a centralized log of data, that is both writable by multiple producers and easily readable by multiple consumers.

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Continuous integration for mobile


Sven Kroell, Mobile QA Engineer at Babbel & Thanos Karpouzis, Senior Android Developer at Babbel held a talk about Continuous integration for mobile at this year’s Droidcon conference.

The video recording is now to available on Youtube.

API versioning at Babbel


Alex MacCaw from Clearbit has written a nice overview about approaches for API versioning. Today we want to elaborate how we deal with API versioning at Babbel.

From the three wide-spread options (using the URL, using a request header, using a dynamic date), we have chosen to go for using URLs. This is the most straightforward solution with minimal overhead for clients.

In addition to a major version, we opted to use a Semantic Versioning approach.

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Babbel @Tech Startup JobsFair 2015 in Berlin

Barbara –

Babbel @Tech Startup JobsFair

Babbel’s Tech and HR teams will be at the Tech Startup JobsFair Berlin Spring 2015 looking for top talents! Babbel is a highly people-oriented company with a strong learning culture. At Babbel, you have the opportunity to work with some of the top talents in the industry, on a highly advanced technology stack that is constantly evolving to keep up with the cutting edge of new developments.

All this is only possible thanks to the team we have put together here at Babbel. Tech team members always participate in the recruitment process, and follow up with mentoring programs for new hires.

Babbel developers take part in great local events and international conferences. Maybe you will be representing us at the next one! But first, come and meet our team at the event, including Boris Diebold, VP Engineering, who will be there to give a quick introduction to the company and answer any questions you may have about working at Babbel.

The Tech Startup JobsFair Berlin is on May 27th 2015, you can sign up now on Eventbrite – and if you’re a top software engineer, we look forward to meeting you there! Check out also our Jobs at Babbel.

Babbel @Tech Startup JobsFair

How to create a radial progress bar with SVG

Jayasurian and Jon –

Radial progress

JS Bin

What is it for?

A while back we implemented a little countdown timer, which involved creating a radial progress bar. We ended up building a SVG radial timer, however we found that a lot of online resources were a bit complicated. In the end we built a straight forward simple radial progress bar using SVG, CSS and JS.

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The 2nd Babbel Hackday - our review


Hack days, hackathons or hackfests are done frequently in IT-companies to bring together engineers, designers and product owners in a playful spirit. The second Babbel Hackday took place on October 24th, 2014 at St. Oberholz – a typical Berlin-Mitte bar we thought…

2nd Babbel Hackday

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MicroXchg 2015 recap


Last week, a lot of Babbel developers attended MicroXchg, the Microservices Conference here in Berlin.

The conference itself was really well-organized. Like really, really well. The speakers were very good, the schedule was audience-friendly (lots of longish breaks to socialize, eat and drink), and the talks were balanced between enthusiastic and down-to-earth.

This post summarizes our impressions and the learnings we returned with.

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