We are developing a real-time event participation system involving limited-capacity sessions, deterministic selection logic, and user balances.

This is not a content website and not a UI-heavy project.
The primary challenge is correctness under concurrency: preventing duplicate actions, inconsistent state, and financial discrepancies.

If your experience is mainly CRUD dashboards or landing pages, this role is likely not suitable.

Responsibilities

• Design authoritative backend services for real-time event participation
• Implement atomic seat reservation and state transitions
• Maintain consistent wallet balances and transaction history
• Integrate and securely process payment webhooks
• Enforce idempotency across critical operations
• Produce auditable logs for dispute resolution
• Coordinate API contracts with mobile client
• Deploy, monitor, and harden the system

Required Competencies

• Strong backend development experience (Node.js, Laravel, or Django)
• Solid SQL knowledge (PostgreSQL/MySQL)
• Deep understanding of transactions, locking, and race conditions
• Ability to design idempotent endpoints
• Authentication and session handling
• Secure handling of external callbacks 
• Defensive programming mindset

Preferred Experience

• Systems involving bookings, wallets, or financial records
• Queue processing / background workers
• Redis or caching layers
• Basic infrastructure & deployment knowledge
  
  Expectations

  The platform handles user balances.
  Incorrect logic directly creates financial loss.

  We prioritize correctness over speed of delivery.
  You should be comfortable reasoning about failure cases before coding.

  Engagement
  • Remote
  • Contract or monthly
  • Initial build phase: ~6–8 weeks
  • Potential long-term involvement post-launch
  Application

  Include:

  • Brief background
  • Preferred stack
  • Example of a system where data integrity mattered and how you ensured it.