Overview

We’re launching Toptal’s next frontier: a borderless finance platform built on stablecoin rails to reinvent how millions of people manage, move, invest, and borrow money. Stablecoins are rapidly evolving into core financial infrastructure, and with regulatory clarity accelerating worldwide, this is the moment to build something foundational. As our founding engineer, you’ll define the technical architecture, ship the first critical systems, and set the culture that future engineers will follow. This is not just another role - it’s your chance to own the technical DNA of a new product from day one.

Responsibilities

• Design and operate systems that move billions in payments globally with near-zero downtime, ensuring sub-100ms latency under peak load.
• Build fault-tolerant APIs and microservices (Node.js/TypeScript), scaling to millions of transactions with observability (metrics, tracing, automated alerts) from day one.
• Embed compliance by design: KYC/AML, fraud detection, and audit trails that don’t slow users down.
• Integrate and secure stablecoin and fiat rails - wallets, orchestrators, on/off-ramps - so anyone, anywhere can send and receive money instantly.
• Ensure backend and frontend choices enhance the user experience, not just the codebase.
• Lead initiatives from design to rollout, balancing ambition with global regulatory realities to deliver reliable systems users can depend on daily.

What you’ll do

• 6+ years building transaction-heavy systems in production, scaling to millions of transactions.
• Deep backend expertise in Node.js (or Java/Go), REST/GraphQL microservices at scale.
• Strong experience with PostgreSQL and Redis.
• Full-stack capability: backend first, but proven ability to ship React/TypeScript frontend features.
• Cloud & infra: AWS/GCP, Kubernetes, CI/CD, IaC.
• Proven ability to meet strict SLAs (99.99% uptime) and latency targets; experience in regulated fintech/payments: compliance, security and UX as one flow.

What we’re looking for

• Design and operate systems that move billions in payments globally with near-zero downtime, ensuring sub-100ms latency under peak load.
• Build fault-tolerant APIs and microservices (Node.js/TypeScript), scaling to millions of transactions with observability (metrics, tracing, automated alerts) from day one.

How you work (values we expect)

• Ownership mindset - you own outcomes, not just tasks.
• Product-minded - you think in flows, not endpoints, and measure impact, not LOC.
• High-velocity, sustainable pace - you ship fast, adapt quickly, and raise the bar every cycle.
• Clarity over complexity - simple for users, even if complex under the hood.
• AI-native builder - you use Cursor/Claude Code/etc. to eliminate grunt work and focus on hard problems.

Bonus Points if you have…

• Scaled stablecoin/payment integrations (wallets, custody, on/off-ramps) to millions of users.
• Hands-on with secure key management, custody infrastructure, or smart contract audits.
• Experience building payment flows handling millions of transactions (cards, payouts, reconciliation, FX).
• Cross-border FX and settlement expertise.

What we offer

• Founding role - build the architecture, standards, and codebase future engineers will inherit.
• Move fast, no bureaucracy - high-trust environment, maximum autonomy.
• Career-defining opportunity - build a payments platform from scratch as stablecoins go mainstream.
• Transparent, supportive culture - feedback flows freely, the best ideas win, and you’ll have the freedom to experiment, learn, and grow.

For Toptal Use Only: #europe #easterneurope

Seniority level

• Mid-Senior level

Employment type

• Full-time

Job function

• Engineering and Information Technology
• Industries: Technology, Information and Internet

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