Backend Staff Engineer - Koinly

Koinly is a successful product used by crypto investors around the world, helping them make sense of complex portfolios and tax obligations across chains, wallets, exchanges, and Defi protocols. The bar is simple to describe and hard to deliver: a user should be able to reconcile thousands of transactions and file their taxes in under 20 minutes.

We're looking for a Backend Staff Engineer to take deep ownership of our data platform - the engine behind products at the intersection of crypto, finance, and tax. You'll own a high-performance, distributed data-processing backend written in modern TypeScript - the system that ingests, normalizes, and reconciles on-chain and exchange data at scale, and turns it into numbers people file taxes with. Correctness is not negotiable here: a wrong balance is a wrong tax return.

This is a senior, hands-on role for someone who combines exceptional engineering craft with genuine product ownership. We expect you to lead by example: writing high-quality code, making sound architectural decisions, and raising the bar for the entire backend team.

We’re a remote-first, async-first startup with deep product-market fit. If you value autonomy, technical excellence, and clear communication over meetings and process complexity, Koinly is the place for you.

Read on for responsibilities, requirements, and who we are.

Role at a glance

Mission: Own the distributed backend data engine end-to-end, guaranteeing precision, performance, and scale for complex crypto tax data.

Location: Remote - Strictly Europe (EU / UK timezones)

Note, we won’t review job applications from outside Europe.

Employment: B2B Contract.

Compensation: USD $80k – $100k/y.

Perks: 32 days PTO (incl. public holidays).

Experience : 8+ years with a focus on complex, data-heavy distributed systems.

Work within one of the most rapidly growing industries in the world

What we're looking for

We're looking for someone who thrives on complex, business-critical financial systems - architectural depth, high throughput, high-volume ETL, and high stakes. You’ll focus on optimising, refactoring, and elevating our backend architecture while ensuring deterministic execution, high availability, and financial-grade correctness.

Above all, we value a high sense of product ownership, exceptional code quality, autonomy, and openness: you take responsibility for outcomes, not just tasks, and you work independently while staying transparent and collaborative.

We also expect:

Deep understanding of distributed system architecture and the design patterns that support it at scale - queues, workers, idempotency, backpressure, rate-limiting, and retries.