Job Details

We are looking for a Senior / Lead Backend Developer to design and develop .NET services, ensure reliability, security, and integrate external APIs. Requires 5+ years of experience, code review, and mentoring experience.

• Design and development of .NET services: application business logic, payment and orchestration flows • Ensuring reliability: idempotency, retries, deduplication, outbox/Saga, failure handling • Ensuring security: secrets/KMS storage, access control, secure configuration and deployment • Integration of external APIs: correct handling of headers/cookies, formats (multipart/x-www-form-urlencoded, JSON), compliance with specifications • Database design (PostgreSQL): schemas, indexes, migrations, query and lock optimization • Work on performance and scalability: profiling, reducing p95/p99, caching, rate limiting • Team management (2-4 developers): task distribution, code reviews, mentoring, onboarding new hires, assisting with blockers • Building an effective development process, implementing code and architecture standards, improving CI/CD and testing practices within the team • Communication with related teams and stakeholders: coordinating integrations with product, analytics, QA, DevOps, agreeing on technical solutions • Regular analysis of problems (incidents, long releases, code disputes), initiating and controlling technical improvements

• 5+ years of experience and at least 1-2 years in a Tech Lead / Team Lead role (or a clear desire and readiness to take on leadership tasks with a strong technical background) • Code review and mentoring experience: ability to provide constructive feedback • Deep knowledge of network protocols and web integrations: HTTP/2, CORS, cookies, multipart/x-www-form-urlencoded • Cryptography and formats: Ed25519, SHA-256, working with binary protocols and byte prefixes • Databases: PostgreSQL, schema design, indexes, transactions, migrations (EF Core) • Microservices and integrations: gRPC/Protobuf, queues/brokers (RabbitMQ/Kafka), Outbox and idempotency patterns • Reliability under load: retries, timeouts, polling, limiters, circuit breaker • Observability: Prometheus/Grafana, structured logging, tracing (OpenTelemetry) • Containerization and CI/CD: Docker, basic deployment and configuration practices • Clean code and architecture: SOLID, unit and integration tests, code reviews, API design Will be a plus: • Experience with anti-bot mechanisms (e.g., Cloudflare: headers, sessions) • Knowledge of DDD and event-driven approaches, Saga/orchestrators, managing transactional boundaries in distributed systems • Experience in payment security and anti-fraud, KMS/Secret management • Experience with property-based testing, load and performance testing, benchmarks