Tom Bartel

You have always been an engineer, solving problems and writing code. Now, there is an opportunity to become an engineering manager. You are interested.

However, questions arise.

With the rewrite of our core product web application, we moved from a PHP/JavaScript tech stack to a Next.js stack. One of the most significant changes for developers was the switch to TypeScript, which most of us had not had a lot of experience with, previously.

From April 2020 until the end of 2021, we have put trivago’s web frontend on a new tech stack. Having moved away from a quite large PHP codebase and our home-grown JavaScript framework Melody, trivago now runs on a Next.js application, written in TypeScript.

trivago open sourced a Prettier plugin for the Twig template language. It is available under the Apache 2.0 license, and you can access it on trivago's Github space.

The trivago core product runs on our own frontend framework Melody. Melody uses a Twig-inspired template language because when it was introduced, it had to be interoperable with our existing codebase, which was based on the Symfony PHP framework with Twig as the default template language.

It was a very special occasion for all JavaScript enthusiasts at trivago: Tobias Koppers, original creator of webpack, and now member of the webpack core team, visited us in our Düsseldorf office. Since we rely on webpack to build not only some very important internal tools, but also our core product, its importance to us cannot be overstated.

Ten participants from nine countries — India, Cuba, Tunisia, England, Poland, Spain, Indonesia, Malaysia, and Brazil. Even on trivago scale, this kind of diversity was impressive.

These were the software developers who were selected for the trivago Tech Camp 2018, an eight-day event taking place at the trivago campus in Düsseldorf, Germany. The event is aimed primarily at IT students, but the admission rules are not terribly strict — basic-to-intermediate coding and problem-solving skills suffice, and many candidates sent in code samples which were so advanced that we were quite impressed. In the end, we also had a physicist on board.

trivago engineering is excited and looking forward to welcoming Kyle Simpson to the spectacular new trivago Campus.

Kyle will give a 5-day JavaScript workshop starting on the 6th of August, 2018. While the workshop is primarily for trivago employees, we want to share this special occasion with the community as well. Therefore, we have reserved three spots for JavaScript enthusiasts who share our love for open source projects.

Imagine a world without open source software. Pretty scary, isn't it?

There would be no free operating systems that let you take full control of your computer.

Education.

It's not only a topic that is very dear to our CEO Rolf Schrömgens, but that trivago as an entire organization cares about. Without good education, we will not be able to continue to add great people to our teams, or advance as a society.

You do not run a successful, stable software project over several years without some amount of automated testing. If several dozens of developers are working on the same code base, the need for test automation becomes even greater. After all, their changes might have unintended effects on other people's code, or on certain edge cases that will not be noticed until the changes go live — and maybe not even then.

Because our main application was getting ever more memory-hungry, our awesome JavaScript architecture team developed a modern, freakishly efficient component and rendering framework which we will open source and highlight in a series of future articles. In order to prove the framework's maturity, we wanted to roll it out to the trivago core application.

With engineers spread across four offices, collaboration and communication in trivago's IT is a challenge. Additionally, new engineers join the company all the time, which makes it even harder to figure out who to talk to about certain products, packages, and technologies.

When publishing a JavaScript library, we usually want to make it available to as many people as possible to maximize the library's usefulness and adoption. In that respect, it can be helpful to users to have the library available in their preferred module format - CommonJS, AMD, ES6, etc. This article shows how to use webpack to automatically export multiple formats without having to maintain them separately.

Twice a year, the trivago software developers gather to have a 2 day internal hackathon. This December saw another round of ambitious creativity, relaxed atmosphere, and good food :-)

One of our core values at trivago is fanatic learning. A great way to learn and expand your knowledge is to creatively try new technologies, or to apply well known technologies to new situations, without having to pay attention to a strict schedule or deadline. Exactly that is what roughly 120 engineers were doing on the first Thursday and Friday in December: It was internal hackathon time, meaning each developer could spend two entire days on their own projects as he or she saw fit.

Learn how we introduced webpack to build our JavaScript assets. One of the main challenges was to run both Assetic and webpack in parallel for some time, in order to run tests and to make sure nothing was broken. This was achieved without any code or configuration duplication by developing a custom webpack loader which was tailored to our setup, and which makes use of transducers.