Senior Backend Engineer

Website Tonsser

Do you enjoy shipping something you brainstormed, architected, designed and built? Are you always striving to find the simplest solutions to the hardest problems? Do you think code that doesn’t have tests is by definition legacy code? Then you sound like the person we’re looking for to join our backend engineering team.
What is Tonsser?
Tonsser is the leading app and platform for youth football players with more than 1.3m players using the app to unlock their potential. The focus has been on building an excellent user experience that motivates, inspires and empowers players to be the best they can be and share it with the community… and discover life-changing opportunities.
With the vision of democratizing the football industry to create equal access to opportunities, we make it possible for players to build identity and capture their performance through stats and video to compare with the community and earn attention from both local and global clubs.
But that is just one part of Tonsser. We know that football is not only about getting discovered, most players have that dream, but play with the objective of having fun with their team. We have built a community that shares our values and aims to revolutionize the next generation of footballers.
Backend engineer at Tonsser
As part of our fast growing football platform, we have many exciting challenges in scaling our backend infrastructure and building new product features for our users.
You will join the Backend Engineering team of Tonsser, the owner of our API, which is used heavily by our client apps (iOS, Android, React). The Tonsser API is built in Ruby on Rails, where we recently hit 100K LOC (with an additional 100K LOC of tests), so it’s a big system. The API is mainly hosted on Heroku, but AWS is also utilized for file storage and video transcoding. We use PostgreSQL as our main database, but also rely on Redis for caching/async jobs and Elasticsearch for search.
Besides working with the current Tonsser REST API, we have are going new ways to scale the Tonsser backend, by creating a new GraphQL API. Tonsser also has a huge scraping setup, run by our Match Data team, and working alongside the API team.
We embrace automated testing (TDD) and over 4.000 tests being run every time a new commit is added to our code base. We use CircleCI for our continuous integration pipeline, which allows us to test new changes quickly and deploy to our production environment several times a day.
When we build something, you’ll be part of the process from brainstorming all the way to shipping, and beyond, to seeing how it performs.
Joining date: November 2020

Requirements for the ideal candidate

    • You have minimum 3 years of experience working as a Backend Engineer
    • You’ve built and architected well crafted and scalable APIs using Ruby on Rails or a similar web framework.
    • Comfortable with REST, JSON and at least a curiosity into GraphQL
    • Experience working with relational databases like PostgreSQL or MySQL
    • Detail-oriented, focusing on writing high quality maintainable code
    • Writing unit and integration tests to ensure that your code is rock solid is a natural part of your workflow
    • Is a team player who strives to improve not only themselves, but everyone around them
    • Values developer productivity by automating as many things possible in your daily workflow
    • Knowledge around running resilient and scalable distributed services
    • Be fluent in English

Benefits (we know you want them)

    • Be part of a company with Multinational DNA, where the official language is English but we speak: Danish, Lithuanian, French, Spanish, Dutch, Serbo-Croatian, German, Polish, Portuguese, Bulgarian and Italian! 🌍
    • Private health care 🚑
    • Personal development budget 🤓
    • 100% Work from home flexibility / Remote Friendly 🏡
    • Free choice of devices and other setups that you need 📱💻
    • Pet friendly office 🐶
    • Donkey Republic membership, so you can explore Copenhagen like a true native 🚲
    • Food and awesome breakfast so make sure you start the day in the best mood, all organic 🍎😱
    • A relocation package for those adventurers ready to take the suitcases! 🗺
    • Monthly gaming nights (pizza included), where we geek out over everything from AEII, CS, Fifa, board games, you name it 🎮
    • Friday bars with beers, sound box, games, and just good times 🍺
    • Regular company trips ✈️
    • Mental health and sport come on the scene! Get a refund for your fitness subscription 🏋🏼‍♀️
    • Look matters too! An agreement with a hairdresser next door to the office will help you to stay flawless!! 💇🏽‍♀️
    • Feel free to arrange private happenings in the office in your free time 🎉
    • Catered, delicious lunch – every single day at 12:00 🌮 (with amazing cake every Thursday 🍰)
    • As startup-as-can-be office loft, just a stone’s throw away from Frederiksberg Centre 🇩🇰
    • Bi-monthly Hackathons, where anyone with even the slightest coding skills can hack away and experiment with new frontiers 👹
About Tonsser
Team of 35 hungry and kind girls and guys. Offices in Paris, London, Germany and HQ in Copenhagen
Backed by international investors and founders of companies like Spotify,, Peakon, Vivino …
Working at Tonsser means you’re working on something very exciting: Shaping the future of football. Through technology we’ve seen a way to impact how new talents get discovered; we’re changing the game of football by placing the power where it belongs: in the hands of the 265 million performers of the sport. For the football players to be in control, they need their own football identity. That’s why we’ve built an app empowering football players to showcase their achievements and determine their success.

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