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Sr. Core Java Developer / Lead

Congensys Corp.Alpharetta, GA🇺🇸United StatesPosted 13 Aug 2026

Quick Overview

Work Type
On Site
Level
Mid Senior

Job Description

Sr. Core Java Developer / Lead

Location: Alpharetta, GA / Menlo Park, CA
Local Candidates Only
W2 Only - No C2C/1099

Job Description

We are seeking a highly skilled Senior Core Java Developer / Lead to design, develop, test, and maintain high-performance, scalable, and reliable enterprise Java applications.

The ideal candidate will have strong expertise in Core Java, object-oriented programming, multithreading, data structures, design patterns, REST APIs, Spring Boot, databases, and enterprise application development.

Required Skills

  • 10+ years of experience in Java software development
  • Strong expertise in Core Java / Java SE
  • Object-Oriented Programming and Design Patterns
  • Collections Framework, Generics, Exception Handling
  • Multithreading and Concurrency
  • Java I/O and NIO
  • Streams and Lambda Expressions
  • JVM Architecture, Memory Management, and Garbage Collection
  • Data Structures and Algorithms
  • Java 8 or later
  • RESTful APIs and backend services
  • Spring, Spring MVC, and Spring Boot
  • Microservices architecture
  • Relational databases such as Oracle, SQL Server, MySQL, or PostgreSQL
  • SQL, JDBC, and ORM concepts
  • Maven or Gradle
  • Git or other version-control systems
  • Unit testing with JUnit, Mockito, or equivalent
  • Agile/Scrum methodology
  • Strong debugging, analytical, communication, and problem-solving skills

Preferred Skills

  • Java 11, 17, 21 or later
  • Kafka, RabbitMQ, JMS, or ActiveMQ
  • Docker and Kubernetes
  • AWS, Azure, or Google Cloud
  • Jenkins, GitHub Actions, GitLab CI, or Azure DevOps
  • MongoDB, Redis, Cassandra, or DynamoDB
  • Distributed systems and event-driven architecture
  • Caching and high-performance application development
  • Application monitoring and observability tools
  • Secure coding and application security
  • Performance testing and profiling
  • Linux/Unix and shell scripting

Key Responsibilities

  • Design, develop, and maintain scalable applications using Core Java
  • Develop multithreaded and high-performance applications
  • Build and consume RESTful APIs
  • Develop modular and reusable backend components
  • Work with relational and NoSQL databases
  • Write efficient SQL queries and optimize database interactions
  • Perform unit, integration, functional, and regression testing
  • Troubleshoot production issues, memory leaks, and performance bottlenecks
  • Participate in code reviews and technical design discussions
  • Contribute to HLD/LLD and implementation plans
  • Integrate applications with CI/CD pipelines
  • Support application deployment, monitoring, and production issue resolution
  • Collaborate with architects, developers, QA, DevOps, product managers, and business stakeholders
  • Participate in Agile ceremonies and sprint activities
  • Provide technical leadership and guidance to development teams

Interested candidates: Please share your updated resume along with your current location, work authorization, and availability.

Skills

Docker
DynamoDB
Microservices
MongoDB
MySQL
Oracle
SQL
SQL Server
Shell
Spring
Spring Boot
AWS
Scrum
Agile
Azure
Cassandra
Git
GitHub Actions
GitLab CI
Google Cloud
JUnit
Java
Jenkins
Kafka
Kubernetes
PostgreSQL
REST
RabbitMQ
Redis

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