Mid-Level Ruby Developer | Remote and Async

Koinly
London

Become part of the backbone of the crypto data flow

At Koinly, we’re looking for a R uby software engineer in the Integrations team, to be the bridge between app development and customer support.

Practically?

☝️ You’ll help keep 900+ crypto integrations running smoothly, so our users don’t have to lift a finger.

We’re 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.

Why this role exists

Koinly connects with a wide range of exchanges, wallets, and DeFi protocols, integrations that are essential to our product. With many already built and APIs constantly changing, this role ensures those connections stay reliable, supports customers when issues arise, and helps deliver a smooth, seamless experience.

It’s about keeping Koinly’s ecosystem stable, up to date, and ready for the fast-moving world of crypto and DeFi.

What you'll do:

You’ll be part of the Integrations squad: the team responsible for keeping Koinly running smoothly across over 900+ crypto platforms. That means a lot of APIs, edge cases, and data quirks. Your work will form the invisible layer that makes crypto tax reporting feel effortless to our users. At the core: Maintain and improve the systems that sync crypto data for 1.5M+ users worldwide.

  • Reproduce, troubleshoot, and resolve complex technical problems (under SLA).
  • Develop new integrations and improve the quality of the existing ones.
  • Monitor and resolve application errors.
  • Add support for new data formats.
  • Partner with Customer Support when technical expertise is needed.
  • You may occasionally be part of an on-call rotation.

What you bring:

  • 3+ years of professional experience with Ruby.
  • Experience integrating third-party services and RESTful APIs.
  • Excellent troubleshooting and problem-solving skills.
  • You like digging through data until things make sense.
  • Able to make pragmatic decisions in complex, ambiguous situations.
  • Clear, concise written and verbal communication in English.
  • Eagerness to work with a high-standard engineering team, CI/CD, and testing.
  • Comfort with feedback loops and a high-ownership mindset.

Why join Koinly

  • A profitable, bootstrapped startup in a hyper-growth industry.
  • Direct access to the founder, an engineer who understands your challenges.
  • Pure Ruby on Rails backend, no language sprawl, no over-engineering.
  • High autonomy, async-first, deep work, minimal meetings.
  • Massive data volume: billions (and billions) of trades, 900+ integrations.
  • Lean team with big impact: millions of users, only 37 people company-wide.
  • No bureaucratic bloat, no corporate theatre.
  • Remote, flexible working hours, async by default.
  • Crypto-adjacent without the hype: we’re a painkiller, not a multivitamin.

Compensation and location

  • Salary range: USD $50,000-$55,000 per year
  • Contract Type: Full-time (Contractor - B2B)
  • Location: Remote [EMEA]
  • Perks:
    • 32 days of PTO
    • Async culture
    • Fast-moving team
    • Founder access
    • The expectation that you own your work

If you’re excited to troubleshoot tough bugs, build integrations, and make an impact for 1.5M+ users while growing your skills fast, this role is for you. Apply now.

Key details in sum

  • Report to: Tech Lead
  • Location: Remote - preference for Europe-based candidates
  • Salary: USD $50,000-$55,000 per year
  • Type: Full-time (contractor - B2B)
  • Experience level: 3+ Years with Ruby
  • Start date: ASAP
  • Team size: 10 engineers in a 37-person company
  • Main responsibilities: Own the full lifecycle of integrations, from troubleshooting and error resolution to building new connectors and supporting customers when issues arise.

Due to the nature of our business and external requirements, we perform background checks on all potential team members, passing which is a prerequisite to join Koinly.

Posted 2025-09-30

Recommended Jobs

Programmatic Solutions Analyst, Programmatic Solutions Consultants - UK

Amazon
London

Description Amazon Ads is dedicated to driving measurable outcomes for brand advertisers, agencies, authors, and entrepreneurs. Our ad solutions - including sponsored, display, video, and custom a…

View Details
Posted 2025-09-21

Commercial Gas Engineer

Calibre Search
Enfield, Greater London

Commercial Gas Engineer An excellent opportunity has arisen for an experienced Commercial Gas Engineer / HVAC Engineer (gas bias) to join one of the country's leading facilities management companies…

View Details
Posted 2025-09-11

IT Business Services Senior Consultant

SAP
Middlesex

We help the world run better At SAP, we enable you to bring out your best. Our company culture is focused on collaboration and a shared passion to help the world run better. How? We focus every da…

View Details
Posted 2025-09-24

Mechanical Technician London

Morson Talent
London

We are currently seeking a Mechanical Technician for our client on a permanent basis centred in London. Department: MEICA and capital maintenance - Our Mechanical, Electrical, Instrumentation, …

View Details
Posted 2025-09-11

Assistant Store Manager

Beauty Retailer
Gants Hill, Greater London

Are you a sales-driven leader with a passion for delivering outstanding customer experiences? Whether you come from retail or hospitality, if you thrive in a fast-paced, target-focused environment and…

View Details
Posted 2025-09-18

HR Business Partner - 12 Month FTC

Wembley, Greater London

HR Business Partner – 12 Month FTC Location: North West London (2 days per week in office) Salary: Up to £75,000 per annum Start Date: Immediate preferred Do you have experience working in…

View Details
Posted 2025-09-09

Teaching Assistant

Reeson Education
Wembley, Greater London

Graduate Teaching Assistant Graduate Teaching Assistant job, Wembley ASD support Potential teacher training Start ASAP Good Rates of Pay The Teaching Assistant Job An outst…

View Details
Posted 2025-09-24

Optometrist

Hayes, Hillingdon, Greater London

Optometrist , Full Time ,Independent Practice , Hayes , Basic salary £50,000-£60,000 depending on experience A well established independent practice is seeking an Optometrist to join them on a fu…

View Details
Posted 2025-09-11