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Senior Ruby Engineer | Remote-first (EMEA) | Crypto Tax

Koinly
London
4 days ago
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As a Ruby Developer, you’ll be responsible for writing clean, modern code that adheres to best practices. We’re looking for a self-motivated individual who takes pride in their work, values high-quality code, and cares deeply about the overall application experience.

We pride ourselves on having very high test coverage and rarely having any prod issues. Our backend follows a microservices architecture, consisting of multiple small services—primarily built with Ruby—that collectively power the user experience.

This role may have on-call responsibilities.

Responsibilities:

  • Design, build, and maintain scalable and efficient Ruby applications.
  • Develop new features and maintain existing code while ensuring high performance and responsiveness.
  • Write clean, maintainable, and efficient code following best practices.
  • Optimize applications for speed and scalability.
  • Implement automated tests and ensure robust code quality.
  • Debug and troubleshoot complex issues across production and development environments.
  • Work closely with product managers, designers, and other engineers to translate business requirements into technical solutions.
  • Stay up-to-date with emerging technologies and best practices in Ruby development.

Requirements:

  • 5+ years of experience with Ruby (bonus points for React)
  • Strong knowledge of SQL databases, query optimizations
  • Excellent problem-solving and debugging skills
  • Experience with RESTful APIs, microservices, and third-party integrations
  • Knowledge of background job processing tools (Sidekiq, etc.)
  • Proficiency in at least 2 programming languages
  • Good written and verbal communication skills in English

Don’t ‘tick all of the boxes? Neither do we. We are driven by hiring not only by experience and relevance for the role but also by ambition. We celebrate anything ‘outside of the box’, so if you don’t meet all of the listed tickbox criteria, please do still apply as we’d love to hear from you.

What we can offer you

Highly competitive package

Fully remote role (with flexible work hours)

32 holidays per annum (incl. public holidays)

Co-working space budget

Work in crypto

Our interview process

  1. An initial call with the hiring manager (30 mins)

  2. A take-home task that is related to the work you would be doing (~3 hours)

  3. A second call that may involve live-coding and architecture problems (1.5 hours)

  4. Final call with the hiring manager (30 mins)

  5. Optionally: There may also be a call with our founder/CEO (30 mins)

About us

At Koinly, we are building software to help crypto investors stay compliant with their tax obligations and keep track of their investments. We launched the first version of our platform in 2019 and have since grown to over 1.5M users by solving a highly technical problem and saving our users countless hours of work (see what our customers say). All of this with a small team of super intelligent and dedicated individuals!

Our values & work environment

As a startup we value efficiency above all else. Our team structure is flat and focused where every individual has a critical role that directly impacts our users. You will not find any middle managers or pointless meetings here. Our environment is best suited for people that are hands-on, like to take ownership and most importantly - are self-learners.

Our team is based in Europe so we try to work in the UK timezone but are flexible on the work timings. Everyone is expected to work 40 hours and no more. We highly value people that can prioritise their work, know what tools to use to work efficiently and can set up processes to amplify the impact of their time.

What to expect in your first month

This is the most decisive part of your tenure at Koinly. You will be assessed on your technical skills and how quickly you are able to become operational. A good benchmark is to try Koinly out yourself, if you have a hard time understanding what it does then things will not get any easier. After all, we expect our users to be able to do their taxes with Koinly in under 20 minutes. An interest in DeFi is a major advantage.


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