About the Role
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.
Responsibilities
•Own the distributed backend data engine end-to-end, guaranteeing precision, performance, and scale for complex crypto tax data.
•Optimise, refactor, and elevate our backend architecture while ensuring deterministic execution, high availability, and financial-grade correctness.
•Work closely with product and engineering leads, serving as a key technical partner to evaluate ideas, propose architectural solutions, and take real ownership of our backend data pipeline.
•Write high-quality code, make sound architectural decisions, and raise the bar for the entire backend team.
Requirements
•8+ years with a focus on complex, data-heavy distributed systems.
•Deep understanding of distributed system architecture and the design patterns that support it at scale - queues, workers, idempotency, backpressure, rate-limiting, and retries.
•Real, production-level DeFi experience - AMMs, lending, staking, LP positions, and bridges. You understand what on-chain activity actually means, and you can spot data anomalies instantly.
•Advanced data modeling and SQL skills, with a track record of tuning performance on massive PostgreSQL datasets.
•Proven professional experience with Rust - you've used it in production or professional settings, can read and write it confidently, and are ready to work in it where extreme performance demands it.
•Fluency with the latest AI development tools such as Claude/Codex/Cursor, and the judgment to put new tools to work effectively in a professional workflow.
•Deep, production-level experience across our core stack:
•Core TypeScript (strict, modern) on the NodeJS runtime, with modern TS tooling (oxlint, oxfmt)
•Distributed processing with RabbitMQ and Redis (ioredis)
•PostgreSQL - schema design, query optimization, and migrations at scale
•node:test for unit and integration testing
•Sentry for error monitoring
•Blockchain libraries and node/indexer APIs; RPC and provider reliability patterns
•On-chain data decoding: ABIs, event logs, traces, token standards, transaction semantics
•Data parsing and wrangling: csv-parse, xlsx (SheetJS), node-html-parser
•Integrations against messy, inconsistent third-party APIs and file formats
•Expert-level TypeScript. You should reach for strong typing instinctively, not as an afterthought.
•Deep Distributed Systems & DeFi context. This is a Staff-level role. You need a deep understanding of async queue architectures, idempotency, and how smart contracts execute on-chain. We need someone who can hit the ground running with a complex, high-throughput pipeline.
Nice to Have
•Public portfolio of projects available on GitHub or similar platforms.
•Deeper Rust experience, especially in performance-critical data processing.
•Background in financial products, double-entry accounting, or tax domains.
•Familiarity with Ruby (our services interoperate with a Ruby codebase).
•Knows and understands our product.
Conditions
•Employment: B2B Contract.
•Compensation: USD $80k – $120k/y.
•Perks: 32 days PTO (incl. public holidays).
•We're a remote-first, async-first startup with deep product-market fit.
•You'll have long blocks of deep work time to actually build.
•You'll own core data services from architecture through deployment and scaling.
•You have the autonomy to make system decisions that stick.
•We don't do unnecessary meetings or processes for the sake of process.
•Due to our domain, background checks are required before joining.
