Senior Back End Developer

  • Backend
  • Permanent
  • London, UK

About the role

We are looking for a Senior Developer to join our new backend services team. You’ll become a core part of a small, dynamic team that is breaking new ground: researching, designing and implementing the future technology at Bark. You’ll be someone who loves innovating and problem solving, and gets a kick out of making systems work efficiently at a continuously-increasing large scale.

Our current back-end technology stack is written in Python and you will need to be able to work within this codebase - but we are at the start of a journey, and your experience will help to shape our technology strategy, adapting our architecture as we grow.

You’ll get the opportunity to utilise a variety of technologies to pave the future of Bark whilst enhancing how we solve complex online problems in cutting-edge areas such as search, classification and core marketplace services. You’ll be involved in every aspect of the process: idea generation, business analysis, technical and architectural design through to implementation.


  • Work with development teams and product managers to conceptualise and implement software solutions
  • Build elegant and performant APIs
  • Develop and manage well-functioning databases and applications
  • Proactively propose and implement improvements to the codebase
  • Design and code solutions for systems with 1000s of transactions a second
  • Work with our data insights team to transform the TBs of data we have, into insights we can use to revolutionise the product

Required skills and experience:

  • Using Python in a production environment
  • Defining, implementing and testing APIs
  • Understand SOLID principles
  • Integrating with 3rd party APIs, including OAuth flows and similar
  • Production MySQL experience; strong SQL skills
  • Using Docker in production, ideally with Kubernetes or Fargate/ECS/EKS
  • Experience building, maintaining, testing and documenting APIs to be used by other developers both internally and externally
  • Strong organisational skills
  • Analytical mindset with numerical aptitude
  • Ability to achieve goals in a highly innovative and fast paced environment

Desired skills and experience:

  • Familiarity with the AWS ecosystem. Knowledge of SQS (or similar such as RabbitMQ), SNS (or Kafka), and how they are used
  • Knowledge of Apache Airflow, Spark, Hadoop and other data toolkits
  • Experience with other data stores like Elastic, MongoDB or similar
  • Interest in machine learning topics such as logistic regression, nlp and others
  • PHP experience with a framework (Laravel, Symfony, Zend, CakePHP etc) would be a bonus, but not essential

Some of our benefits:

  • Competitive salary
  • Share options in a rapidly growing company, whose founders have a proven track record of successful exits
  • Private gym, just for Bark employees
  • Private health insurance
  • Monthly socials and massive parties
  • Fully stocked kitchen and weekly team lunches

What our devs say...

Henry, Tech Team Lead - “It’s an exciting time to join Bark in many ways but especially from a tech point of view, because we’re at the beginning of the biggest architectural transition in the company's history. As we transition from a startup to a much larger company, we need to upgrade our stack from a few monolith systems, to much more scalable, maintainable, decoupled services.”

George, Developer- “Working so closely with the product and design teams gives me an opportunity to get involved in the product from the earliest stage. Each week we build a new experiment which is a true collaboration of the ideas from everyone in the group. Due to the scale of Bark as a business, it’s also hugely rewarding to see that the work we produce can make a massive impact, by generating millions of pounds in annualised revenue.”

Tom, Senior Product Designer - “There's a real sense of camaraderie across the company. The tech side of the business is really exciting at the moment – we broke into different teams and the effect is phenomenal. Never a dull moment, and feels like we're making real measurable change to the product for our users!”