We are looking for a hands-on Senior Backend Engineer — Node.js/TypeScript to build Our platform's application and API layer.
You will own backend services, business logic, APIs, third-party integrations, asynchronous workflows, and application-level security and transaction controls.
You will work closely with our Lead Full Stack Platform Engineers, Senior PostgreSQL Database Engineers, Frontend Developers, and product/architecture team.

This is not an architecture-only role. We are looking for someone who designs systems and then builds them.

What You'll Do
Design and build production backend services using Node.js and TypeScript
Build secure, well-defined and versioned REST APIs
Implement authentication, authorization and role-based access controls
Build tenant-aware services and enforce multi-tenant authorization boundaries
Develop investor, issuer/property, onboarding, transaction, portfolio, wallet and marketplace backend workflows
Integrate external KYC/KYB and identity providers
Integrate with Fireblocks custody/wallet infrastructure
Build payment, banking and other external service integrations
Implement secure webhook ingestion, callback processing and external/internal ID mapping
Design idempotent transaction workflows and protect against duplicate processing
Implement retries, exponential backoff, rate-limit handling, reconciliation and failure recovery
Build asynchronous workflows using queues/background jobs
Implement Redis-based caching and other distributed application patterns where appropriate
Work with the PostgreSQL Database Engineer on schema requirements,



transaction boundaries and query patterns
Use Prisma ORM while understanding when database-specific approaches are required
Protect PII and financial data in transit and at rest
Implement structured logging, monitoring and application observability
Write unit, integration and API tests
Participate in code reviews and establish maintainable backend engineering standards
Work with AWS-based infrastructure and containerized deployments

Required Qualifications
4–8+ years of professional backend software engineering experience
Robust recent production experience with Node.js and TypeScript
Strong experience designing and implementing production REST APIs
Experience building authentication and authorization systems, including JWT/OAuth and RBAC
Hands-on experience integrating complex third-party APIs involving:
authentication/token management
webhooks
callbacks
rate limits
retries
failure recovery
Experience implementing idempotency for transactional APIs or workflows
Solid PostgreSQL knowledge and experience working with relational databases
Experience with Prisma, TypeORM or comparable ORM technology
Experience with asynchronous/background processing
Production experience with AWS and Docker




Robust understanding of application security, secrets management and protection of sensitive data
Experience with Git-based workflows, automated testing and CI/CD

Preferred
Fintech, payments, investment, digital assets or other regulated-platform experience
KYC/KYB integrations such as Sumsub or equivalent
Fireblocks or other institutional custody/wallet API experience
Redis
SQS, RabbitMQ, BullMQ, Kafka or similar messaging/queue technology
AWS ECS, RDS, S3, IAM, Secrets Manager and CloudWatch
OpenAPI/Swagger
OpenTelemetry, Datadog, Grafana or similar observability tools
Experience building multi-tenant SaaS platforms
Experience using AI-assisted engineering tools such as Claude Code, Cursor or GitHub Copilot while independently reviewing and validating generated code

What You Are Not Expected to Own
You should be comfortable working with PostgreSQL, but you are not expected to be our PostgreSQL performance specialist . Advanced schema architecture, query-plan optimization and database performance engineering will be owned by the Senior PostgreSQL Database Engineer.
Blockchain smart-contract development, including Solidity/ERC-3643, is a separate specialist function.

What Success Looks Like
You can take a business workflow such as investor onboarding or a transaction lifecycle, define the API and backend architecture, work with the database engineer on the data contract, implement it securely, integrate the required external services, test it, and take ownership of its behavior in production.

📌 Senior Backend Engineer — Node.js/TypeScript (Dona Paula)
🏢 MeridianSquare
📍 Dona Paula