Senior Java Backend Developer

Quantum Technologies. LLC; McLean (VA); On-site; USD 150,000 - 190,000; Full time

Job summary

Quantum Technologies. LLC in McLean, VA is seeking a highly experienced Backend Engineer to design, develop, and maintain enterprise-grade backend systems using Java and Spring Boot.

You will own end-to-end backend feature lifecycles, implement RESTful APIs, and ensure secure, scalable inter-service communication. Collaborating with frontend, DevOps, QA, and product teams, you will drive architectural planning, perform code reviews, mentor junior developers, and uphold coding standards and

Qualifications

• 10+ years of backend development experience with Java (8+).
• Deep expertise in Spring Framework (Boot, Data, Security).
• Microservices architecture and API design experience.
• Experience with SQL databases (PostgreSQL, MySQL) and NoSQL stores (MongoDB, Redis).
• Docker and Kubernetes experience; CI/CD pipelines.
• Security principles: OAuth2/JWT, encryption.
• Strong problem-solving and communication skills.

Responsibilities

• Lead end-to-end lifecycle of backend features from design to deployment.
• Develop RESTful APIs and secure inter-service communication.
• Optimize performance, reliability, and scalability.
• Collaborate with frontend, DevOps, QA, and product teams.
• Conduct code reviews and mentor juniors.
• Participate in architecture and technical strategy.
• Troubleshoot complex production issues.

Skills

Java

Spring Boot

Microservices

REST API

CI/CD

Security

Tools

Docker

Kubernetes

PostgreSQL

MySQL

MongoDB

Redis

Kafka

RabbitMQ

JUnit

Mockito

Job description

Design, develop, and maintain enterprise-level backend systems and microservices using Java (Spring Boot).

Lead the end-to-end lifecycle of backend features - from technical design and implementation to deployment and support.

Develop RESTful APIs and ensure secure and efficient communication between distributed systems.

Optimize system performance, reliability, and scalability.

Integrate with relational and NoSQL databases and ensure data integrity and optimal access patterns.

Collaborate with frontend, DevOps, QA, and product teams to deliver integrated and high-quality solutions.

Conduct code reviews and provide technical mentorship to junior and mid-level developers.

Participate in architectural planning, technical strategy, and design discussions.

Ensure adherence to coding standards, best practices, and security guidelines.

Troubleshoot and resolve complex technical issues in production and staging environments.

Required Skills:

10+ years of backend development experience, with deep expertise in Java (Java 8 or later).

Strong hands-on experience with Spring Framework (Spring Boot, Spring Data, Spring Security, etc.).

Solid understanding of microservices architecture, API design, and integration patterns.

Experience with SQL databases (e.g., PostgreSQL, MySQL) and NoSQL stores (e.g., MongoDB, Redis).

Proficient in RESTful API design and implementation.

Hands-on experience with unit testing (JUnit, Mockito) and CI/CD pipelines.

Experience working with Docker, and familiarity with container orchestration platforms like Kubernetes.

Good understanding of application security principles, including authentication (OAuth2, JWT), authorization, and encryption.

Familiarity with message brokers (Kafka, RabbitMQ) and asynchronous processing.

Excellent problem-solving, analytical, and communication skills.

We are an equal opportunity employer. All aspects of employment including the decision to hire, promote, discipline, or discharge, will be based on merit, competence, performance, and business needs. We do not discriminate on the basis of race, color, religion, marital status, age, national origin, ancestry, physical or mental disability, medical condition, pregnancy, genetic information, gender, sexual orientation, gender identity or expression, national origin, citizenship/ immigration status, veteran status, or any other status protected under federal, state, or local law.