At trivago we use Jenkins as our main CI tool. However, when our physical setup was not enough we needed to move it to the cloud and implement an automated slave scaling. This is the definite guide with all the steps we took to implement an auto scaling Jenkins platform.

Concepts like separation of concerns, logic decoupling or dependency injection are things we developers have heard more than a couple of times. At trivago, the Android app is developed using the Model View ViewModel (MVVM) architecture, aiming for views as dumb as possible, leaving the decision making to the view models. This leads to an increased test coverage since testing logic in views is something we can’t do that easily.

For our products, like the trivago hotel search, we are using Redis a lot. The use cases vary: Caching, temporary storage of data before moving those into another storage or a typical database for hotel meta data including persistence. The main parts of the hotel search are built with PHP and the Symfony Framework for the frontend (web) and Java for the backend part. In this article, we will focus on the collaboration between our PHP application and Redis. Both are running fine, but it was a long and hard way up to the current situation. This is the story of how we learned to use Redis, including our failures and experience.

At trivago we have been using code reviews as a part of our process for a good while now. In the beginning they weren’t used by many teams but as word of their positive impact spread, more and more teams started adopting this practice, benefiting every day from its many advantages. Like any new practice it has been a learning process from the start. In this blog post I will cover why code reviews are incredibly beneficial when done right and will share what we have learned and which best practices we employ.