Talent Network: Senior Backend Engineer (Node.js)

## About the Role As a Senior Backend Engineer at Toptal, you will play a crucial role in building and scaling the backend for a borderless neobank on stablecoin rails. This involves working across traditional banking integrations, blockchain infrastructure, and card issuance, ensuring every transaction is correct and every workflow survives a crash. You will be part of an agentic-first engineering team, utilizing AI-assisted tooling daily to drive efficiency and innovation. The team's focus on correctness over speed, codified standards, and test-driven development (TDD) encourages a culture of quality and reliability. With the neobank operating on stablecoin rails, the ability to design idempotent activities and deterministic workflows is crucial for maintaining the integrity of financial operations. ## What You Will Do - Design and implement scalable backend systems using Node.js and NestJS - Develop and maintain PostgreSQL databases, including schema design, transactions, and performance tuning - Implement event-driven architecture patterns, such as outbox/inbox, to ensure reliable transaction processing - Work on temporal workflow design for critical financial operations, ensuring crash-resilience and idempotency - Develop and maintain GraphQL APIs using Apollo Server, including resolvers, custom scalars, and pagination - Integrate webhooks with signature verification, inbox pattern, and IP whitelisting for secure communication - Participate in the evolution of the event-driven architecture, ensuring observability and incident response for payment flows - Collaborate with the team to maintain high-quality code, using automated reviews, MCP integrations, and Claude Code - Implement retry policies, non-retryable error classification, and failure handling in distributed systems - Ensure transaction boundaries in distributed systems, maintaining the integrity of financial data ## What We Are Looking For - Strong proficiency in Node.js and TypeScript, with experience in NestJS - Experience with PostgreSQL, including schema design, transactions, and performance tuning - Knowledge of GraphQL API design and implementation using Apollo Server - Understanding of event-driven architecture and distributed systems - Familiarity with fintech domain, including payment rails, double-entry accounting, and KYC/KYB compliance flows - Experience with Solana ecosystem, stablecoin mechanics, and blockchain infrastructure - Proficiency in cryptographic signing and wallet custody models - Ability to work with AI-assisted coding tools, such as Claude Code, and maintain code quality - Experience with observability and operations tools, such as Datadog, Sentry, and Pino/Winston ## Nice to Have - Experience with Privy, Sumsub, Noah, or Rain APIs - Knowledge of AWS KMS and HSM-backed signing - Familiarity with PostgreSQL logical replication and NestJS module architecture - Experience contributing to internal developer tooling, such as custom slash commands and MCP servers ## Benefits and Perks - Remote work arrangement with a dynamic and innovative company - Opportunity to work on cutting-edge projects in the fintech and blockchain space - Collaborative and supportive team environment - Access to the latest AI-assisted coding tools and technologies - Professional development opportunities, including training and conference sponsorships - Competitive compensation and benefits package - Flexible working hours and vacation policy - Access to a global network of professionals and experts in the field

- Tip: Showcase your experience with Node.js, PostgreSQL, and event-driven architecture in your resume and cover letter.

• Tip: Be prepared to discuss your approach to designing idempotent activities and deterministic workflows in distributed systems.
• Tip: Highlight your proficiency in GraphQL API design and implementation, as well as your understanding of fintech domain and blockchain infrastructure.
• Tip: Demonstrate your ability to work effectively in a remote setting, with experience in collaborative tools and communication platforms.
• Tip: Prepare examples of your experience with AI-assisted coding tools, such as Claude Code, and how you maintain code quality in your work.
• Tip: Research Toptal's unique approach to agentic-first engineering and be prepared to discuss how you can contribute to this approach.
• Tip: Be ready to discuss your salary expectations and negotiate based on your experience and qualifications.