Job Opening:

Principal Back-end Developer - Ruby (Home-based)

Be part of a progressive, open and productive workplace, where different opinions and beliefs are valued.

Get on board with the fastest-growing cybersecurity company in the UK.

We're a game-changing team building a game-changing platform


About Immersive Labs

Immersive Labs enables organizations to evidence their cyber capability, risk and resilience across technical and non-technical teams for the first time. Our platform gives you the ability to measure real-time cyber efficacy as it relates to cyber teams, developers, engineers and executives. All in one platform, kept up to date at the speed of cyber. We call this Cyber Workforce Optimization.


Where we are now

Immersive Labs was founded in 2017, from a cargo container in Bristol, UK we’ve grown to over 300 employees globally and announced funding of more than £80 million. Our technology is already enabling organisations including KPMG, Sophos and the NHS to measure, map to risk, and optimise the human cyber abilities of their entire workforce.

We encourage people of all different backgrounds and identities to apply. We are committed to maintaining an inclusive, supportive place for you to be you and do your very best work.


The opportunity

We are putting together a team to develop a new product and seek a highly talented and experienced Ruby / Ruby on Rails engineer to join us as a Principal Ruby Engineer to support the rapid growth of our Engineering team. You will get the opportunity to work in a cross-team capacity, solving hard technical problems, design architectural improvements, while constantly looking for ways to develop other engineers. 

You will become a key member of our technical leadership team alongside 2 other Principal Engineers in the current engineering team you'll collaborate to define and execute our long-term technical strategy, with the goal of creating a highly stable, secure, scalable and extensible platform.

You will also get access to our platform, and on top of this, you will have a personal technical skills budget.  

There will be plenty of opportunities to learn new skills and technologies as you'll get to work in a friendly multi-disciplinary agile team and also work on innovative ideas you want one day a fortnight in 10% time - which we call Trailblaze Time. This is a whole day once every 2 weeks to innovate and explore new tools and technologies.     


Your main responsibilities (we're scaling fast, so these may change as we grow):

You'll get to immerse yourself in Ruby, Ruby on Rails, Docker, Kubernetes and AWS. We want to give you a place where you'll learn from us and we'll learn from you through getting involved in the following:

  • Being a resident expert in all things Ruby / Ruby on Rails, advocating for and implementing best practices and patterns that ensure an efficient, reusable and reliable codebase
  • Delivery of large, mission critical engineering projects
  • System design and architectural improvements, including the creation of PoCs / RFCs to validate proposed changes
  • Coaching / mentoring and pairing with engineers and being an ambassador for Immersive Labs at external events and conferences
  • Defining the long-term technical strategy based on current and future needs
  • Improving developer experience by reducing toil e.g. local development set up, CI/CD improvements, test suite optimisation etc.
  • Proactively identifying problems, scoping possible solutions and championing prioritisation with Engineering Managers and Product Managers

Success in this role will depend most on your approach, underlying skills and potential for growth, even if some of the above would be new to you. You should apply if you have ​​(we know it’s tough, but please try to avoid the ​​confidence gap​.​​ You don’t have to match all the listed requirements exactly to be considered for this role):

  • Extensive experience with Ruby, Ruby on Rails, GraphQL, object-oriented design, containers / Kubernetes and AWS
  • Demonstrable, and up-to-date knowledge of the Ruby language, RSpec, RoR, MySQL and object-oriented programming principles
  • A strong ability to communicate complex technical problems to a wide range of audiences both written and verbal
  • Experience designing and creating database schemas that represent and support complex business processes
  • Experience scaling a monolithic application codebase with fast growing customer and developer headcounts
  • Proficient in the architecture of distributed systems piecing together cloud services such as databases, queues, and event buses


Immersive Labs’ growth has been fuelled by our values that underpin everything we do, here's how they relate to this role:

  • Inclusive - we create an environment of psychological safety
  • Driven - we all have the same goal, to be a must have in every company's defence against cyber attacks
  • Agile - we are a scaling organisation which means things change. Constantly.



What Immersive Labs offers:


As well as an inclusive, supportive place for you to be you. We offer an extensive range of benefits so you can do your very best work:

  • Time off, flexible and remote working so you can work when is best for you, includes 25 days annual leave +  2 volunteering days and birthday half day
  • Look after your family and yourself with enhanced parental leave, mindfulness groups, critical illness cover, pension, health plan and more. 
  • Career and learning development through the platform and our ‘Learn Anything’ fund
  • Recognition & Rewards for doing great work and living our values and behaviours
  • Informal or formal flexible working options, e.g. flexible start and finish times, reduced hours, job share, remote working
  • We’re a sociable, tight-knit team with monthly socials, sports clubs and quarterly parties. Our socials have included everything from pottery painting and paper mask making, to movie nights and escape rooms.
  • When you do visit the UK hub getting there is easy: we’re based in the centre of Bristol, just a 10 minute walk from the train station. We also offer railcard loan and cycle scheme to buy a new bike


Find out more at


Cyber threats wait for no one and neither should you. Apply now!


What you can expect once you apply:

  • Our talent acquisition team review all applications received which can take up to two weeks to complete
  • If successful, you will receive an invite from a Talent Acquisition Partner to a screening interview which takes around 30 minutes to discuss the role, culture at Immersive Labs and your expertise in more detail.
  • If you progress from this step there will be 3 interviews involving . a cultural interview, technical coding assessment and system/architectural presentation Your Talent Acquisition Partner will outline each step when you get there
  • If at any point you are unsuccessful we will advise you. From application we do this via email and due to volumes we can not respond individually to every applicant. From 1st Interview onward, we endevour to call you with feedback.

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.