Senior Backend Integration Engineer (Node.js)- English Required

This is not a low-code configuration role. It requires deep understanding of backend engineering, protocols, concurrency, and security.

Role Overview

We are looking for a Senior Backend Engineer with a strong focus on integrations, capable of designing, implementing, and maintaining robust, scalable, and secure backend systems, primarily using Node.js, APIs, and event-driven architectures.

What You’ll Do

Design and implement robust backend integrations across multiple systems (SaaS, APIs, internal services) Build and maintain secure, scalable REST APIs Design and operate event-driven systems (webhooks, async processing, retries, idempotency) Implement authentication and authorization flows: OAuth2 (authorization code, client credentials) JWT (token validation, security considerations) API Keys / HMAC when needed Handle real-world integration challenges: duplicated events out-of-order data partial failures Debug and resolve production issues across distributed systems Ensure proper logging, monitoring, and error handling Participate in technical decision-making and trade-offs

4+ years of backend experience Strong experience with Node.js (deep understanding of async I/O and event loop behavior) Solid understanding of HTTP protocol and API design Proven experience designing and operating webhooks in production, including: idempotency handling retries and failure recovery event deduplication Experience implementing OAuth2 flows, including: authorization code client credentials token lifecycle and refresh tokens Strong understanding of JWT beyond basic usage (signing, validation, security implications) Experience working with production systems under real constraints