Tandem is the mobile community for learning languages. We believe that speaking a language from day one is the fastest way to become fluent. Our vision is a world where people are empowered to teach each other any language.

Tandem has experienced high growth since its launch in 2015, with over 2m global downloads and 60,000 active users daily. Our achievements include being recognized by Apple as the “Most Innovative iPad App of 2015” and as the only German app on the international list of the “Best Apps of 2015”.

We believe that speaking a language from day one is the fastest path to become fluent. As a Backend Engineer at Tandem you will help to shape how the next generation of language learners reaches fluency.



    • Developing new features and maintain existing functionality from day one
    • Creating and scaling a technologically ambitious, optimized, high performance server-side codebase, API and and administration user interface
    • Working as part of an experienced team of designers, client and fullstack engineers
    • Helping to shape and continuously improve our engineering practices and processes
    • Being a sparring partner for architecture and technology decisions for our lead engineers on the client and backend side



  • At least two years of professional experience in in a backend or fullstack engineering role
  • An excellent command of PHP framework architectures (Zend or alternative framework with standardized ORM/ActiveRecord implementation)
  • RDBMS (MySQL, PostgreSQL, or other), database (de)normalization, SQL/NoSQL (Redis/Memcached)
  • Coding standards (PSR) and code naming conventions
  • A passion for agile software development best practices, agile principles, CI/CD and TDD to build scalable, well-tested, and maintainable software
  • Have worked with git vcs
  • Knowledge of KISS and what SOLID is
  • Belief in yourself as a professional engineer


  • Inter process communication (RPC, WebServices, Soap, Protocol Buffers, etc.)
  • Realtime communications (sockets, websockets/nodejs, xhr, comet or other server push alternatives)
  • Beanstalkd or other queues (SNS, Gearman, Memcacheq…)
  • Message brokers (RabbitMQ, ApacheMQ) or alternative wire messaging protocols experience (AMQP, MQTT, STOMP)
  • Deployment & build automation
  • AWS infrastructure
  • Machine learning-as-a-service platforms such as Amazon Machine Learning
  • Experience working with Firebase, GCM, APNS services
  • Asynchronous PHP frameworks (react, icicle.io, amphp, swoole…)
  • Phalcon or HHVM in production loads
  • Penetration testing and load testing
  • Knowledge of and enthusiasm about golang, swift, elixir and typescript


    • The chance to join a friendly, highly experienced and exceptionally talented team early on
    • Competitive remuneration
    • An inspiring loft office in one of Berlin’s start up hotspots
    • Free access to our language teachers on Tandem
    • Free choice of your IT setup
    • Team lunches, excursions, drinks, great coffee, office snacks, etc.
    • You’ll probably learn how to say “Hi” in 20 more languages…!


    If this sounds like the right next step, we’d love to hear from you! Please send an email with your CV / resumé and salary expectations to jobs@tandem.net