Full-Stack Developer

• Develop and maintain backend services using TypeScript, Node.js, and NestJS.


• Investigate production incidents involving duplicate payments, failed transactions, payment gateway outages, and security key issues.


• Identify root causes, propose solutions, and implement fixes in collaboration with the Tech Lead.


• Optimize PostgreSQL or MySQL queries, indexes, transactions, and database performance.


• Work with microservices communication, distributed transactions, and high-load processing scenarios.


• Implement and maintain reliable transaction flows, including idempotency and failure handling.


• Analyze data, monitor system performance, and improve application stability.


• Deliver planned development tasks and system enhancements.


• Participate in code reviews and contribute to engineering standards.


• Handle occasional frontend development tasks using React.


• Join the on-call rotation when the 24/7 SLA is introduced.

Requirements

• 3+ years of commercial software development experience.


• 3+ years of hands-on, commercial NestJS experience in a production environment.


• Strong TypeScript and Node.js skills. Express-only experience does not meet this requirement.


• Experience with PostgreSQL or MySQL, including:
  
  
  
  • Complex SQL queries and query optimization
  
  
  • Indexing and performance tuning
  
  
  • Database transactions and concurrency considerations
  
  
  
  


• Basic React or Next.js experience and willingness to contribute to frontend tasks.


• Practical experience supporting or implementing high-load systems, such as:
  
  
  
  • Database and transaction optimization
  
  
  • Distributed transactions and Saga patterns
  
  
  • Identifying bottlenecks and reliability issues
  
  
  
  


• Understanding of microservices architecture and its trade-offs.


• Understanding of payment idempotency, monitoring, and testing practices.


• Experience investigating production issues and implementing corrective actions.


• Ability to work independently, take initiative, and communicate technical issues clearly.