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

At Koinly were looking for a Senior Ruby Developer to help design build and maintain scalable backend systems that power crypto tax reporting for over 1.5 million crypto investors. Youll write clean efficient and high-performance code not to just ship new features but to continuously optimize speed reliability and user experience across our Ruby (and Ruby on Rails)-powered architecture.Were a fully remote-first async-first startup with product-market fit in a niche (and booming) domain: crypto taxes. If you value autonomy technical excellence and clear communication over meetings and process complexity Koinly is the place for you.Key role detailsDepartment: TechLocation: EMEA preferably EuropeSalary: USD $80000-$90000 per yearType: Full-time remote (Contractor – B2B)Timezone: Ideally UK 2 hoursTeam size: 10 engineers in a 35-person teamAbout us Were on a mission to make crypto taxes simple.Since 2019 weve grown to 1.5M users by tackling one of cryptos messiest challenges: tax reporting. Our platform helps investors stay compliant track their assets across hundreds of wallets exchanges and DeFi platforms and save hours of time. Just see what our customers have to say about us.Behind that focus towards simplicity lies a deeply technical product built on large-scale data processing and 900 integrations. Our stack is Ruby-heavy our test coverage is high and our expectations on code quality and system performance are even higher. The roleAs a Sr. Ruby Developer youll be responsible for writing clean modern code that adheres to best practices. Were 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 that collectively power the user experience.If you have a data mindset a sharp eye for clean scalable code a bias for ownership and want to work in the fast-growing crypto space apply now!What youll do:Design build and maintain scalable Ruby microservices used across the Koinly platform. Work with massive datasets billions of transactions and millions of users with a focus on database optimization and performance.Refactor large code bases to remove complexity.Debug and troubleshoot complex issues across production and development environments.Own and implement new product features end-to-end.Maintain existing code while ensuring high performance and responsiveness.Write clean maintainable and efficient code following best practices.Implement automated tests and ensure robust code quality.Once in a while youll have on-call responsibilities.Stay up-to-date with emerging technologies and best practices in Ruby development.What youll bring:6 years of professional Ruby experience.Strong SQL skills including performance tuning and complex queries.Strong problem-solving and debugging skills you leave code better than you found it.Experience working with RESTful APIs microservices and third-party integrations.Familiarity with background job processing tools (Sidekiq etc.).Proficiency in at least 2 programming languages.Eagerness to work with a high-standard engineering team CI/CD and testing.Clear concise written and verbal communication in English.Youre based in Europe and have experience working remotely in async environments.Comfort with feedback loops and a high-ownership mindset.Bonus points for:React experience.Interest in DeFi blockchain or emerging languages like Rust is a major advantage.What youll get:A lean no-BS engineering environment with high-trust and high-impact engineering environment with zero fluff that ships with quality.Flat operations with full ownership and autonomy.An async-first work environment that favors clear communication and documentation over meetings. Focused deep work we respect your time energy and limits.A role where every line of code you write has a direct user impact.A culture that values feedback autonomy and outcome-driven workUSD $80$90K per year (B2B contract).32 paid days off per annum (incl. public holidays).Remote and async-first work environment.Co-working space budget if desired.Your first monthYour first few weeks at Koinly are all about mutual discovery. Youll receive hands-on tasks that help us understand your technical strengths and how you operate in our async-first ownership-driven environment. At the same time youll get to explore whether our way of working challenges and supports you in the right ways.Were big on clarity autonomy and getting things done and we hold our own product to the same standards. We expect our users to get their taxes done in under 20 minutes and we aim to build with that same focus and confidence. A good benchmark Try Koinly yourself. If the product doesnt click for you quickly building it wont be easier.Our interview processAn initial call with the talent team (30 mins).A take-home task (3 hours).Technical interview with live-coding and architecture problems (90 mins).Final call with the founder (30 mins).How to applyReady to join a lean async-first team building real-world tools for the crypto space Were looking for clarity ownership and technical sharpness.Click Apply for this job to submit your CV. Key Skills Tax Experience,Accounting Software,GAAP,QuickBooks,Accounting,Sage,Account Reconciliation,Analysis Skills,Research Experience,SOX,Microsoft Excel,Financial Analysis Employment Type : Full Time Experience: years Vacancy: 1