Lead Software Engineer
Toptal.com
Office
Europe, Eastern Europe, UK
Full Time
Get ready to· Collaborate daily with product, design, and compliance in a lean, cross-functional team.· Drive product decisions end-to-end, moving from concept to code to production in days, not months.· Contribute to technical excellence: architecture reviews, RFCs, and open feedback - building practices that scale.· Influence not just the codebase, but the direction of the platform itself - shaping how millions of people will move money globally.
What you’ll do· 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 we’re looking for· 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 target (<100ms). *Experience in regulated fintech/payments: compliance, security and UX as one flow.
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.
What you’ll do· 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 we’re looking for· 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 target (<100ms). *Experience in regulated fintech/payments: compliance, security and UX as one flow.
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.
Lead Software Engineer
Office
Europe, Eastern Europe, UK
Full Time
October 3, 2025