Senior Full-Stack Developer (TypeScript, NestJS, React)

Balancify is building a next-generation FinTech crypto-banking platform that powers acquiring, payouts, and corporate card solutions for businesses.
You will work on scaling a high-load financial system used by real companies every day — solving complex technical challenges, optimizing performance, and shaping a product where your engineering impact truly matters. 🚀

We are looking for a Senior Full-Stack Developer experienced with TypeScript, NestJS, and React, capable of working with large real-time data streams and designing scalable system architecture.

Tech stack

Backend: TypeScript, NestJS, MySQL/PostgreSQL, Docker, WebSockets

Frontend: React, CSR/SSR balancing concepts, Tailwind, WebSockets, State-management
Other: Architectural patterns, algorithms, database design & optimization, unit/integration/e2e testing

Responsibilities

Backend

• Develop and scale high-load backend services using NestJS
• Design scalable architecture, complex modules, and business-critical flows
• Implement advanced FinTech algorithms and transaction logic
• Build and optimize relational databases (MySQL/PostgreSQL)
• Improve performance through optimized SQL queries and indexing
• Write unit, integration, and e2e tests
• Work with Docker and containerized environments

Frontend

• Build and maintain user-facing applications using React
• Ensure smooth performance and responsiveness under high load
• Work with large real-time data streams (WebSockets)
• Implement scalable state management across the app
• Convert UI/UX designs into performant and maintainable components
• Collaborate closely with backend engineers for seamless integration

Requirements

• 5+ years of experience with JavaScript/TypeScript
• Strong commercial experience with NestJS and large-scale enterprise architecture
• 3+ years of professional experience using React in production
• Deep understanding of JS/TS internals
• Experience working with high-load systems and real-time data
• Strong knowledge of architectural patterns, algorithms, and system design
• Experience with SQL schema design, optimization, and complex queries
• Proficiency with Docker and testing practices

• Strong analytical and problem-solving skills

   

  Nice to have

• Experience with Web3/Blockchain (even basic integrations)
• Experience integrating banking APIs or financial services
• Previous experience building banking/payment platforms
• Knowledge of security principles, cryptography, consensus algorithms
• English — Intermediate+
  
  What Balancify offers:
• Competitive compensation
• Flexible working schedule
• 30 working days of paid annual leave
• A complex FinTech product with real high-load engineering challenges
• Opportunity to influence architecture and technical decisions
• Professional growth, mentorship, and learning support
• Access to corporate education and internal knowledge bases
• Compensation for certifications and learning initiatives
• Corporate social responsibility initiatives