Senior Backend Software Developer

So Energy

  • Full Time

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We are changing things. We are So Energy, a fast-growing 100% renewable energy supplier in the UK. We’re the leading energy supplier for customer service. We’ve won a host of awards too; in each quarter since 2017 we’ve been recognised by Citizens Advice as a top ranked supplier out of a total of 50. We’ve also won the 2020 Moneyfacts Energy Provider of the Year award and been recognised as a Which? recommended energy supplier for 2020.

We have a heterogeneous tech stack including Ruby on Rails, Python, NodeJs & Kotlin. We are converting our existing platform to a microservices architecture using Kotlin, Kubernetes and Google Cloud with the objective being a robust, performant, scalable and maintainable system that goes far beyond just our website.

We need someone who has a clear understanding of software engineering practices and agile development. Someone who has experience with different technologies and is able to quickly learn and adapt to new ones. Someone who can help in technical decisions but that genuinely enjoys constructive technical debates.

The successful candidate must be comfortable working alone, or as part of a team, and will help the team in converting legacy scripts, mechanisms and services into more maintainable microservices following development best practices & developing proofs of concept for projects of an RnD nature.

Sound like you? Then please read on!


What you’ll be doing

  • Help develop scalable and reliable systems based on microservice architecture (using Kotlin, Kubernetes and Google Cloud)
  • Use software engineering best practices including:
    • Applying OOP patterns
    • Applying clean architectural practices
    • Write automated unit and integration testing
    • Code refactoring
    • Code review
    • Applying good application security practices
  • Plan, design and develop new features for different systems, extending or creating new microservices
  • Actively proposing new ideas about how to solve specific problems or improve the systems we currently have
  • Reporting into the Head of Engineering, you will take ownership of the feature to develop, proactively looking for improvements and proposing new implementation approaches
  • You’ll help others on their development pathway and mentor less experienced developers

Candidate Profile:

  • You are comfortable working alone, but are equally comfortable and enjoy working with a multidisciplinary agile team formed of Backend developers, Frontend developers, Product Manager, QA engineers.
  • Professional experience writing microservices ideally in Kotlin (or Java)
  • Excellent knowledge of software engineering practices in particular applied to backend, infrastructure and deployment in the cloud
  • We are looking for candidates with some experience with at least 2 of the following languages: Kotlin, Java, Ruby, Python, NodeJs, C++, Go
  • Experience or desire to work in a fast pace environment, with a growing number of cross functional teams
  • Experience or desire to modernise and streamline legacy systems
  • GIT versioning
  • Automated tests
  • Collaborative, you are able to mentor less experienced developers

It would be great, but not essential, if you have experience with the following:

  • Kotlin (or Java)
  • Experience with transitioning from monolithic to microservices
  • Kubernetes
  • Google Cloud or AWS
  • Microservices on GCP or AWS
  • Experience with Agile methodologie


What’s in it for you?

  • Competitive salary and performance related bonus
  • 25 days holiday, plus bank holidays, and an extra day holiday for your birthday
  • Perkbox
  • Ongoing support and development as well as a generous learning and devlopment budget
  • Free daily breakfast
  • Last Friday of each month nibbles and drinks in the office
  • Cycle to work scheme
  • Excellent transport links
  • Great reward and recognition
  • Exposure to all parts of a growing business
  • Pension matching as part of auto-enrolment pension scheme

This role will be working from home two days a week. The other 3 days will be from our office in Chiswick. In order to successfully work from home, any candidate for this role will need to have:

(a) A safe, private and distraction free environment from which to work in the UK;

(b) A strong internet connection with a minimum download speed of 10mbps and an upload speed of 3 mbps;

(c) A smartphone

During Covid-19 restrictions, all our employees are able to work from home

So Energy care about helping the energy industry become a much more diverse and inclusive environment and we work hard to lead by example. We are committed to Equal Employment Opportunity and building an inclusive environment for all.

If you are interested in finding out more please apply making sure to complete all the questions to the best of your ability and attached an up to date version of your CV.

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