Backend Engineer (Service Platform)

About

Job Summary

A ​backend ​engineer ​who builds ​the foundation every other ​team ​depends on.

Next ​Securities builds stable ​trading infrastructure ​and ​scalable services ​with ​a ​technology-centric mindset.

We are ​in ​the early stages ​of ​designing ​and implementing new ​platform systems, ​and ​we are ​at a ​point ​where we can ​define superior ​technical standards without the constraints of the existing structure. We are a team where engineers proactively design and complete the direction of the platform in an environment requiring high throughput, real-time data, multi-tenant reliability, and high availability. Service Platform Team's services sit on the critical path of every product team, therefore the quality of our design directly shapes the velocity and stability of the entire engineering organization

Responsibilities

· Design, development, and operation of platform services, such as notifications, market data, experimentation, the API gateway, and AI agents.
· Design and enhancement of architecture for large-scale event processing, real-time data streams and high-fan-out workloads
· Domain model and data design that ensure correctness, consistency, and reliable delivery across shared services
· Non-disruptive deployment, real-time monitoring, and continuous improvement of the failure response system
· Standardization of service structure through event-driven architecture and reusable common modules
· Participation in establishing a long-term technology roadmap and structural design for next-generation trading infrastructure

*In the process of building a new system together, engineers stand at the center of technical decision-making and directly participate in structural design from a long-term perspective.

[Technology Stack]
· Language / Framework: Kotlin/Java, Spring Boot
· Infra / Tools: Kafka, Redis, Kubernetes, Docker, AirFlow, ELK, Grafana
· Database: PostgreSQL, Oracle
· Ops: Establishing automated deployment, service monitoring, and log analysis environments

Requirements

· Over 5 years of backend development experience
· Experience in designing and operating service architectures based on Java, Kotlin, and Spring Boot
· Experience in large-scale, high-throughput processing and performance optimization
· Experience in RDBMS or NoSQL design and performance improvement
· Experience building distributed architectures using Kafka, Redis, and messaging/caching systems
· Disaster response and non-disruptive deployment experience for a stable operating environment
· Business-level English proficiency (reading, writing, and verbal collaboration)

Preferred

· Experience designing and operating shared platform services or developer-facing APIs with multiple user groups
· Experience in designing and operating systems where reliability and delivery guarantees are critical (notifications, data pipelines, gateways, or similar high-availability services)
· Service development experience in the financial domain or mission-critical environments
· Experience in designing and operating event-driven architecture or microservices architecture
· Experience operating cloud-based (AWS/GCP) infrastructure
· Experience in building CI/CD, test automation, and operations automation environments
· Experience with real-time service failure monitoring and emergency response
· Experience with LLM/AI-agent application infrastructure

Benefits

[For Local]
· Health check ~! We cover your annual health screenings.
· We support employees with various life events (weddings, funerals, etc.)!
· Get medical expense reimbursements through our group accident insurance.
· A welfare card you can spend however you like.
· Sit back and relax — employee loan program available.
· Cash benefits provided for holidays, Family Month, Christmas, and more ~!