Senior Backend Engineer – Distributed Systems & API Architecture

Talenzon; Greater London; On-site; GBP 100,000 - 140,000; Full time

Job summary

Talenzon is seeking a Senior Backend Engineer to join our London on-site team. You will design and implement robust backend services for high-availability applications, focusing on distributed systems, API design, and cloud-native delivery.

You will work on RESTful APIs, event-driven systems, and scalable microservices, with emphasis on performance, resilience, and maintainability. Strong Java/Spring Boot experience and experience with Docker/Kubernetes are required.

Qualifications

• 6+ years of professional backend software engineering experience.
• Strong Java and Spring Boot expertise.
• Experience designing microservices and distributed systems.
• Strong knowledge of REST API design, OpenAPI, and API security.
• Experience with relational databases, SQL, and query optimization.
• Hands-on experience with Docker and Kubernetes.
• Knowledge of messaging systems such as Apache Kafka.
• Experience with automated testing, CI/CD, and Git-based workflows.
• Understanding of observability, distributed tracing, and production troubleshooting.
• Excellent English communication skills.

Responsibilities

• Design, develop, and maintain backend services using Java and Spring Boot.
• Build modular, maintainable applications based on microservices and domain-driven design.
• Define service boundaries, integration patterns, and API contracts.
• Develop asynchronous processing workflows and event-driven services.
• Participate in architecture reviews and technical design discussions.
• Design and implement RESTful APIs and OpenAPI specifications.
• Implement authentication and authorization using OAuth 2.0 and OpenID Connect.
• Integrate backend services with databases, messaging systems, and external APIs.
• Apply API versioning, rate limiting, request validation, and error-handling standards.
• Develop automated API tests and integration test suites.
• Implement reliable inter-service communication and fault-tolerance patterns.
• Apply timeouts, retries, circuit breakers, and idempotency controls.
• Use Apache Kafka for asynchronous messaging where appropriate.
• Design services to handle concurrent workloads and partial failures.
• Investigate production incidents and resolve performance bottlenecks.
• Package applications using Docker and deploy workloads to Amazon EKS.
• Build automated delivery pipelines using GitHub Actions.
• Provision supporting infrastructure with Terraform.
• Implement application observability using OpenTelemetry, Prometheus, and Grafana.
• Improve deployment reliability and operational readiness.
• Develop unit, integration, and contract tests.
• Conduct code reviews and promote clean code and secure coding practices.
• Identify and resolve memory, latency, database, and concurrency issues.
• Maintain technical documentation and production runbooks.

Skills

Backend engineering

Java

Spring Boot

Distributed systems

REST API design

OpenAPI

CI/CD

Git workflows

Observability

English communication

Tools

Docker

Kubernetes

OpenTelemetry

Prometheus

Grafana

GitHub Actions

Terraform

Kafka

Job description

We are looking for a Senior Backend Engineer with strong experience in distributed systems, API design, and cloud-native application development to join our client’s on-site team in London.

This role focuses on designing and implementing robust backend services for high-availability applications. You will contribute to architectural decisions, develop scalable APIs and event-driven services, and improve the performance, resilience, and maintainability of production systems.

What You'll Do

Backend Architecture & Development

• Design, develop, and maintain backend services using Java and Spring Boot.
• Build modular, maintainable applications based on microservices and domain-driven design principles.
• Define service boundaries, integration patterns, and API contracts.
• Develop asynchronous processing workflows and event-driven services.
• Participate in architecture reviews and technical design discussions.

API Engineering & Integration

• Design and implement RESTful APIs and OpenAPI specifications.
• Implement authentication and authorization using OAuth 2.0 and OpenID Connect.
• Integrate backend services with databases, messaging systems, and external APIs.
• Apply API versioning, rate limiting, request validation, and error-handling standards.
• Develop automated API tests and integration test suites.

Distributed Systems & Resilience

• Implement reliable inter-service communication and fault-tolerance patterns.
• Apply timeouts, retries, circuit breakers, and idempotency controls.
• Use Apache Kafka for asynchronous messaging where appropriate.
• Design services to handle concurrent workloads and partial failures.
• Investigate production incidents and resolve performance bottlenecks.

Cloud-Native Delivery

• Package applications using Docker and deploy workloads to Amazon EKS.
• Build automated delivery pipelines using GitHub Actions.
• Provision supporting infrastructure with Terraform.
• Implement application observability using OpenTelemetry, Prometheus, and Grafana.
• Work with platform engineering teams to improve deployment reliability and operational readiness.

Quality & Engineering Standards

• Develop unit, integration, and contract tests.
• Conduct code reviews and promote clean code and secure coding practices.
• Identify and resolve memory, latency, database, and concurrency issues.
• Maintain technical documentation and production runbooks.

What We're Looking For

Required Skills & Experience

• 6+ years of professional backend software engineering experience.
• Strong Java and Spring Boot expertise.
• Experience designing microservices and distributed systems.
• Strong knowledge of REST API design, OpenAPI, and API security.
• Experience with relational databases, SQL, and query optimization.
• Hands-on experience with Docker and Kubernetes.
• Knowledge of messaging systems such as Apache Kafka.
• Experience with automated testing, CI/CD, and Git-based workflows.
• Understanding of observability, distributed tracing, and production troubleshooting.
• Excellent English communication skills.

Nice to Have

• Experience with Amazon EKS and AWS infrastructure.
• Knowledge of Terraform and GitOps.
• Experience with PostgreSQL, Redis, and database performance tuning.
• Familiarity with OpenTelemetry and distributed tracing.
• Experience with high-traffic SaaS platforms or financial services.

Location: London, UK Work Model: On-site Role Type: Full-Time