Friday is Tryday

Janina Cußmann
rebuy recommerce
5 min readFeb 10, 2023


“Friday is Tryday” in our Tech teams.

Every Friday, our engineers can attend to a topic they consider important and want to push forward. This can be about their personal career development, staying up to date, learning something new, improving the codebase, or working on product improvements they believe in.

We asked our engineers what they did during their recent trydays. Here you’ll find their answers:

Armin Telker, Senior App Engineer

“Last tryday I was investing time into chatgpt to understand the impact of this tool in our daily working life. It will change a lot in the future. This tryday I was learning some skills around working on our silos (microservices) to take a look beyond my iOS and Android core expertise. This is helping me to understand other dev teams better and gives me a better solid ground in my daily discussions around topics out of the direct mobile scope.”

Filip Kjamilov, Junior iOS Mobile Engineer

“During tryday, I was able to explore new ideas and ways to enhance our iOS App. With the help of ChatGPT, I had a lot of fun discovering its capabilities and finding new ways to work with it to improve our product. The experience not only helped me to become more confident and knowledgeable about integrating ChatGPT into my daily work, but it also allowed me to actively participate in the critical and creative process of enhancing our iOS App. It’s great that we have the time and resources to challenge and motivate our product for continuous improvement.

In the next tryday, I want to focus on utilizing ChatGPT to write good and stable UNIT tests. I believe that with its language capabilities, ChatGPT can assist me in writing tests that are both effective and efficient, ensuring the stability and quality of our iOS App. I’m excited to dive deeper into this aspect of integration and see how it can streamline the testing process for me.”

Mazin Ahmed, Senior Backend Engineer

“During my trydays, I focus on exploring and learning new programming languages that are not frequently used in my current role but are widely used in our company. For example, one of the most interesting trydays I had was when I learned Golang. This experience helped me expand my skillset and deepen my understanding of different programming languages.

I have been interested in Golang for a long time, and finally having the opportunity to learn it during my try day was exciting. The reason I found it particularly intriguing is that our company heavily uses it, which made me eager to gain hands-on experience with it. Furthermore, I was impressed by its impressive performance and wanted to explore it further in a real-world production environment: there was a project started by our Head of Engineering a while ago but was kept in the backlog due to a lack of resources and priority to pick it back up.

The project is about an internal tool for generating our website sitemaps and publishing them to Google Search Console.

It was a well-known fact that the current process of it takes countless hours, given it needs to go through millions of products, and we could save some computing resources and money if we were to rewrite that hence it got started back then.

I got onboarded to that project, and within a matter of a couple of weeks, I was able to bring it to the finish line and push the tool to production. What took hours now takes less than 30 mins to compute the same amount of products :)”

Martin Parsiegla, Senior Backend Engineer

“In the last trydays, I added the open source dashboard sorry cypress. We are now running our cypress integration tests against this newly added dashboard, which makes it easier to see what is happening in the tests.

My goal here was to make the developer experience better, as previously it was quite cumbersome to find out why an integration test failed.

With this new dashboard, every developer can now take a look at a recorded video and see what was happening during a test. In addition, screenshots are taken if a test fails, so you can see the exact state of the webpage at that time.”

Andres Guzman, App Engineer

“I really enjoy having the time to work on the things that might not seem urgent, but ultimately make the app and the code a little bit better every time you invest on it. I’ve reduced a lot of code debt during the trydays and also implemented very nice and user oriented features that made life easier for our customers, e.g. having a good resolution full screen image for the selling product page and implementing the pull to refresh feature in some important places, just to name a few.

I use this day also to test some assumptions that otherwise would be considered wasted time. This output helps me decide on whether I want to move forward with a certain idea, or simply call it a day and take the learnings with me for my next experiment.”

An App Engineer

“I tried out Compose, it went so well that now we use compose in almost every screen, we also took some time on the trydays and refactored old code to Compose. I spent time improving build time to save time on other days.”

Ota Mares, Head of Engineering — Web & Apps

I used the last trydays to ramp up Googles Server-side tagging. Now we are running their tagging server in our data center and continue to migrate all client-side pixels to the server, reducing the pollution for our customers and lowering the risk of breakage.

My goal was to reach a balance between tracking requirements and a great website experience, these two worlds don’t come well together.

With this setup, our marketing has the freedom they need to run any number of cooperations, all without the fear of interfering with the website performance or usability.

Amine Jebbour, App Engineer

“During my trydays I learned and practiced Compose, migrated many views to Compose, and refactored old code. Nowadays most of our Views are in Compose, and we have less and less legacy code. Trydays are a great opportunity to learn, improve and keep the knowledge and skills up to date.”