Java Full Stack - US Cit/GC Only

zAnswer LLC
Chicago, IL

Role: Java full stack Developer

Location is Chicago, IL (5 days onsite)

Job Type: Contract

Duration: Long Term

Banking domain experience is mandatory.

Location – Chicago

Exp – 8 years plus.

Description: Full Stack Developer (Java, Spring Boot, Microservices, Kafka, Cloud, Cassandra, Reactive/WebFlux)

Position Overview

We are seeking an experienced Full Stack Developer with strong expertise in Core Java, Advanced Spring Boot, Microservices architecture, Kafka, Cloud Technologies, Cassandra, and Reactive Programming (WebFlux). This role involves building high-performance backend microservices and scalable front-end applications, contributing to system design, and delivering enterprise-grade solutions.

Key Responsibilities

Backend Development

  • Develop, enhance, and maintain Spring Boot microservices using Core Java and advanced Spring features.
  • Implement Reactive Programming using Spring WebFlux, Reactor, and non-blocking I/O patterns.
  • Build scalable REST APIs, asynchronous communication flows, and event-driven components.
  • Integrate and work extensively with Kafka for event streaming, pub/sub, and message processing.
  • Design and implement distributed systems with high availability and resiliency.

Frontend Development

  • Develop responsive, user-friendly UI applications using React / Angular / Vue (based on project needs).
  • Integrate frontend applications with backend APIs and microservices.
  • Ensure modular, reusable components and consistent design patterns.

Cloud & DevOps

  • Deploy and run microservices on major cloud platforms: AWS / Azure / GCP.
  • Utilize Docker, Kubernetes, Helm for containerization and orchestration.
  • Build and maintain CI/CD pipelines (Jenkins, GitHub Actions, Azure DevOps, GitLab).
  • Implement observability—logging, monitoring, tracing—using ELK, Prometheus/Grafana, Splunk, or Cloud-native tools.

Data & Storage

  • Design and optimize Cassandra data models, queries, and partition strategies for large-scale datasets.
  • Use Spring Data Cassandra (Reactive) to build reactive persistence layers.
  • Integrate additional data platforms like Redis, RDBMS, or NoSQL stores as needed.

Architecture & System Design

  • Contribute to design discussions and create scalable, secure microservices architecture.
  • Follow 12-factor, cloud-native, and domain-driven design (DDD) principles.
  • Apply security frameworks (OAuth2, JWT, Spring Security) across services and APIs.

Quality & Collaboration

  • Write clean, well-tested code using JUnit, Mockito, Testcontainers, and contract testing.
  • Participate in code reviews, architectural discussions, and pair programming.
  • Work closely with product owners, architects, and cross-functional teams in an Agile environment.

Required Skills & Experience

Technical Skills

  • 5–10+ years of hands-on experience in Core Java (Java 8–21).
  • Advanced-level expertise in Spring Boot, Spring Cloud, WebFlux, Reactive Streams.
  • Strong experience building microservices with distributed systems and RESTful APIs.
  • Hands-on experience with Kafka (producers, consumers, streams, schema registry).
  • Solid knowledge of Cassandra with performance tuning and data modeling.
  • Front-end development experience using React / Angular / Vue.
  • Strong understanding of concurrency, multithreading, and non-blocking programming models.

Cloud & DevOps Skills

  • Experience working with AWS, Azure, or GCP cloud architectures.
  • Proficiency with Docker, Kubernetes, Git, CI/CD pipelines.
  • Understanding of distributed tracing, observability, service mesh is a plus.

Soft Skills

  • Strong analytical, debugging, and problem-solving skills.
  • Excellent communication and teamwork abilities.
  • Self-driven and capable of leading full-stack solutions independently.

Preferred Qualifications

  • Knowledge of Kafka Streams, ksqlDB, or event-driven microservice patterns.
  • Experience with GraphQL, API Gateways (Kong, Apigee, or Spring Cloud Gateway).
  • Cloud or Java certifications (AWS, GCP, OCI, Java, K8s).
  • Prior experience with serverless or micro-frontend architectures.
Posted 2026-01-19

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