Core Java Developer

Gresham

Noida, Uttar Pradesh, India

Job Purpose

As a Core Java Engineer, you will play a key role in designing, developing, and maintaining high-performance, scalable enterprise applications. You will work closely with engineers, architects, and cross-functional teams to deliver robust software solutions aligned with business and technical objectives.

The role has a strong focus on Core Java, Spring, application performance, scalable architecture, distributed systems, and engineering excellence, with opportunities to leverage modern AI technologies to improve development productivity and software quality.

Key Responsibilities

Design, develop, and maintain high-performance, scalable applications using Core Java and Spring/Spring Boot.
Write clean, maintainable, reusable, and well-tested code following SOLID principles, clean code practices, and TDD.
Apply strong knowledge of OOP, Design Patterns, Data Structures, Collections, Generics, Exception Handling, and Java 8+ features.
Work extensively with multithreading, concurrency, synchronization, thread pools, and asynchronous programming.
Develop and maintain RESTful APIs and backend services using Spring Boot and Spring REST.
Design and implement scalable solutions using microservices and distributed-system principles.
Analyse and optimise application performance, including CPU, memory, threads, garbage collection, JVM behaviour, and network performance.
Troubleshoot complex production issues and perform root-cause analysis and performance tuning.
Design and optimise relational databases such as Oracle, including SQL queries, stored procedures, indexing, and database performance.
Build automated unit and integration tests using JUnit, Mockito, and related testing frameworks.
Participate in technical design, code reviews, architecture discussions, and engineering best-practice initiatives.
Work with Git, Maven, CI/CD pipelines, DevOps tooling, and cloud environments, particularly AWS or equivalent.
Leverage AI-assisted development tools such as GitHub Copilot, ChatGPT, or Amazon CodeWhisperer to improve development efficiency and code quality.
Explore and integrate AI/LLM services where appropriate to solve business and engineering problems.
Collaborate effectively with architects, engineers, QA, product teams, and other stakeholders within an agile environment.Essential Skills & Experience
5+ years of professional experience in Java development, with strong expertise in Core Java.
Strong hands-on experience with Java 8/11/17+.
Good understanding of:
OOP and SOLID principles
Collections Framework
Generics
Exception Handling
Java Streams and Lambda Expressions
Multithreading and Concurrency
JVM internals and memory management
Garbage Collection
Design Patterns
Data Structures and Algorithms
Strong experience with Spring Framework and Spring Boot.
Hands-on experience developing REST APIs and backend services.
Good understanding of Microservices and distributed application architecture.
Strong experience with Oracle/SQL, database design, query optimisation, indexing, and stored procedures.
Experience with JUnit, Mockito and automated testing.
Strong knowledge of Git, Maven, CI/CD and DevOps practices.
Experience working with AWS or other cloud platforms.
Strong debugging, troubleshooting, performance optimisation, and problem-solving skills.
Experience working in an Agile/Scrum development environment.
Excellent communication and collaboration skills.Desirable Skills
Experience with high-volume, low-latency applications and distributed systems.
Strong understanding of JVM profiling and performance tuning.
Experience with caching technologies such as Redis.
Experience with messaging/event-driven technologies such as Kafka, RabbitMQ, or similar.
Experience with Docker and Kubernetes.
Knowledge of AWS services and cloud-native architecture.
Experience with observability tools for application monitoring and troubleshooting.
Scripting/automation experience with Python, Bash, or PowerShell.
Experience using AI/LLM tools for coding, testing, documentation, code reviews, or developer productivity.
Experience contributing to technical architecture and design decisions.Equal Opportunities Statement

At Gresham, we are committed to building a diverse and inclusive workforce that reflects the communities we serve. We encourage applications from individuals of all backgrounds and strive to create a workplace where everyone feels valued, respected, and supported.

We make employment decisions based on merit, skills, and potential and do not discriminate based on any protected characteristic. We are also committed to making reasonable adjustments throughout the recruitment process and employment lifecycle.

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