How (not) to sink a data stream to files? Journeys from Kafka to Parquet.

By Gabor Hermann on 30-07-2018
Category: Development Tags: Java Scalability BigData Open source distributed

Last year the Measuring 2.0 team at bol.com has started measuring user behavior on the bol.com website. Of course, we wanted to make the data widely accessible within the whole organization.

Making sense of the user agent string

By ir. drs. Niels Basjes on 30-03-2017
Category: Development Tags: Java Open source UX DataScience

Ever since I’ve started working for a WebAnalytics company in 2005 I’ve been working on problems related to making sense of web data. One of the most difficult elements in this type of analysis is making sense of the user agent.
Very often the raw web data I work with is stored in Apache HTTPD access log files that have been compressed using gzip.

My baby was leaky and now it’s not

By Roy Jacobs on 7-02-2017
Category: Development Tags: Hazelcast Java

When you build a service at bol.com your responsibility doesn’t end once the build is green. You’re actually supposed to run it (and keep it running) in production, too. Luckily, our team doesn’t have to do this all by ourselves: there are platform and infrastructure teams to turn to and other development teams to harass over coffee. It’s a bit like caring for a newborn baby I suppose: you try to do a lot yourself but when the baby starts crying for the first time you’ll need all the help…