Java Developer - Lead

We are looking for a Senior Backend Engineer with a strong background in building distributed, scalable, and high-performance backend systems. The ideal candidate has 6+ years of backend engineering experience, including 3+ years in microservices or distributed architecture, and deep expertise in Python, FastAPI, PostgreSQL, Redis, and async I/O patterns.

The candidate will own backend services end-to-end — from architecture and design to implementation, optimization, and production support — while working closely with cross-functional teams to deliver mission-critical systems.

Key Responsibilities

1. Backend Architecture & Development

• Architect, design, and implement backend services using Python (preferably FastAPI) with clean, maintainable, and scalable code.
• Develop microservice components, service communication layers, and distributed workflows.
• Build APIs and backend modules optimized for performance, fault tolerance, and low latency.

2. Distributed Systems & Scalability

• Design and maintain distributed systems capable of handling high throughput and large-scale operations.
• Implement inter-service communication patterns (REST, event-driven, message queues, pub/sub).
• Ensure system resiliency through redundancy, graceful degradation, and autoscaling strategies.

3. Asynchronous & Event-Driven Architecture

• Build async workflows, background tasks, and pipeline services leveraging asyncio or async frameworks.
• Develop event-driven components including producers, consumers, and event processors.
• Optimize I/O-heavy operations to maximize concurrency and throughput.

4. Data Storage, Pipelines & Caching

• Design relational schemas, write optimized SQL queries, and work with PostgreSQL performance tuning (indexes, partitions, query planning).
• Implement caching strategies, rate limiting, distributed locks, and session storage using Redis.
• Build data validation pipelines and compliance-driven data flows ensuring data correctness and auditability.

5. Security, Reliability & Observability

• Implement authentication, authorization, encryption, and secure API practices.
• Build monitoring, alerting, metrics, and tracing systems using modern observability tools.
• Diagnose production issues, identify bottlenecks, and drive long-term fixes and improvements.

6. Code Quality & Technical Leadership

• Conduct detailed code reviews and ensure engineering best practices across the team.
• Participate in technical roadmap planning, architectural discussions, and system design decisions.
• Mentor junior and mid-level engineers; drive a culture of technical excellence and ownership.

Required Qualifications

• 6+ years backend engineering experience.
• 3+ years building microservices or distributed systems.
• Strong expertise in Python and frameworks like FastAPI (or Flask/Django with async exposure).
• Deep understanding of async I/O, concurrency models, and asynchronous programming in Python.
• Strong experience with PostgreSQL (schema design, advanced queries, optimization).
• Hands-on experience with Redis for caching, queues, session management, and distributed patterns.
• Experience with event-driven architectures, message processing, or streaming systems.
• Solid understanding of system design, scalability principles, and API lifecycle management.
• Experience working with CI/CD pipelines, containerization (Docker), and cloud environments.

Java Developer – Job Description

Wissen Technology is now hiring for a Java Developer - Bangalore with hands-on experience in Core Java, algorithms, data structures, multithreading and SQL. We are solving complex technical problems in the industry and need talented software engineers to join our mission and be a part of a global software development team. A brilliant opportunity to become a part of a highly motivated and expert team which has made a mark as a high-end technical consulting. Required Skills: • Exp. - 5 to 12 years. • Experience in Core Java and Spring Boot. • Extensive experience in developing enterprise-scale applications and systems. Should possess good architectural knowledge and be aware of enterprise application design patterns. • Should have the ability to analyze, design, develop and test complex, low-latency client facing applications. • Good development experience with RDBMS. • Good knowledge of multi-threading and high-performance server-side development. • Basic working knowledge of Unix/Linux. • Excellent problem solving and coding skills. • Strong interpersonal, communication and analytical skills. • Should have the ability to express their design ideas and thoughts. About Wissen Technology: Wissen Technology is a niche global consulting and solutions company that brings unparalleled domain expertise in Banking and Finance, Telecom and Startups. Wissen Technology is a part of Wissen Group and was established in the year 2015. Wissen has offices in the US, India, UK, Australia, Mexico, and Canada, with best-in-class infrastructure and development facilities. Wissen has successfully delivered projects worth $1 Billion for more than 25 of the Fortune 500 companies. The Wissen Group overall includes more than 4000 highly skilled professionals. Wissen Technology provides exceptional value in mission critical projects for its clients, through thought leadership, ownership, and assured on-time deliveries that are always ‘first time right’. Our team consists of 1200+ highly skilled professionals, with leadership and senior management executives who have graduated from Ivy League Universities like Wharton, MIT, IITs, IIMs, and NITs and with rich work experience in some of the biggest companies in the world. Wissen Technology offers an array of services including Application Development, Artificial Intelligence & Machine Learning, Big Data & Analytics, Visualization & Business Intelligence, Robotic Process Automation, Cloud, Mobility, Agile & DevOps, Quality Assurance & Test Automation. We have been certified as a Great Place to Work® for two consecutive years (2020-2022) and voted as the Top 20 AI/ML vendor by CIO Insider. 

• Develop, enhance, and maintain Java-based applications using Spring Boot and related frameworks.
• Design, implement, and optimize Microservices with RESTful APIs.
• Build and manage Spring Batch jobs, including scheduling, chunk processing, partitioning, and error handling.
• Apply object-oriented design (OOD) and GoF design patterns (Factory, Singleton, Strategy, Observer, etc.).
• Write clean, maintainable, and scalable code following best coding standards.
• Integrate applications with databases (SQL/NoSQL) and messaging systems (Kafka/RabbitMQ).
• Participate in code reviews, technical discussions, and architectural decisions.
• Troubleshoot production issues and ensure application performance, scalability, and reliability.
• Work in an Agile/Scrum environment and collaborate with cross-functional teams.

Technical Skills Required

• ** Core Java 8+**, OOP, Collections, Multithreading
• ** Spring Boot**, Spring MVC, Spring Data JPA
• ** Spring Batch** (Job/Step configuration, Tasklets, Readers/Writers, partitioning)
• ** Microservices** (REST, API Gateway, service discovery, resilience patterns)
• ** Design Patterns** (Factory, Singleton, Adapter, Strategy, Builder, Observer, etc.)
• ** Databases:** MySQL/PostgreSQL/Oracle, MongoDB (optional)
• ** Messaging:** Kafka / RabbitMQ (preferred)
• ** Build tools:** Maven/Gradle
• ** CI/CD:** Jenkins, GitLab CI, or similar
• ** Cloud:** AWS / Azure / GCP (optional but preferred)
• ** Testing:** JUnit, Mockito

Role overview

1) Overall 5 to 7 years of experience. Node.js experience is must.

2) At least 3+ years of experience or couple of large-scale products delivered on microservices.

3) Strong design skills on microservices and AWS platform infrastructure.

4) Excellent programming skill in Python, Node.js and Java.

5) Hands on development in rest API’s.

6) Good understanding of nuances of distributed systems, scalability, and availability.

Egen is a data engineering and cloud modernization firm helping industry-leading companies achieve digital breakthroughs and deliver for the future, today. We are catalysts for change who create digital breakthroughs at warp speed. Our team of cloud and data engineering experts are trusted by top clients in pursuit of the extraordinary. An Inc. 5000 Fastest Growing Company 7 times, and recently recognized on the Crain’s Chicago Business Fast 50 list, Egen has also been recognized as a great place to work 3 times.

You will join a team of insatiably curious data engineers, software architects, and product experts who never settle for "good enough". Our Java Platform team's tech stack is based on Java8 (Spring Boot) and RESTful web services. We typically build and deploy applications as cloud-native Kubernetes microservices and integrate with scalable technologies such as Kafka in Docker container environments. Our developers work in an agile process to efficiently deliver high value data driven applications and product packages.

Required Experience:

• Minimum of Bachelor’s Degree or its equivalent in Computer Science, Computer Information Systems, Information Technology and Management, Electrical Engineering or a related field.
• Have experience working and strong understanding of object-oriented programing and cloud technologies
• End to end experience delivering production ready code with Java8, Spring Boot, Spring Data, and API libraries
• Strong experience with unit and integration testing of the Spring Boot APIs.
• Strong understanding and production experience of RESTful API's and microservice architecture.
• Strong understanding of SQL databases and NoSQL databases and experience with writing abstraction layers to communicate with the databases.

Nice to have's (but not required):

• Exposure to Kotlin or other JVM programming languages
• Strong understanding and production experience working with Docker container environments
• Strong understanding and production experience working with Kafka
• Cloud Environments: AWS, GCP or Azure

• Experience - 6-10 years
• Key Skills for Software Developer C++, Linux with SQL:
• - Looking only for candidates who can join immediately or max 10 day
• - should be able to work independently with no handholding
• - the ability to work with C/C++ code on Windows/Linux platforms
• - Database knowledge of MSSQL, Oracle, MySQL/MariaDB, ideally other ones too: Saphana, Teradata, Postgres.
• - Ability to work on their own fixing defects
• - should be able to understand secure coding practices
• - should have the Ability to work independently and with the team across different time zones

• Writing reusable, testable, and efficient code.
• Design and implementation of low-latency, high-availability, and performant applications
• Integration of user-facing elements developed by front-end developers with server-side logic
• Implementation of security and data protection
• Integration of data storage solutions

Skills And Qualifications

• Practical knowledge and understanding of web applications.
• 3+ years of good hands-on experience in Python, with knowledge of Django
• Good hands-on experience in SQL Database (MYSQL / Postgres)
• Knowledge of user authentication and authorization between multiple systems, servers, and environments
• Able to create database schemas that represent and support business processes.
• Strong unit test and debugging skills
• Proficient understanding of code versioning tools GIT.
• Has experience of working in an Agile Environment. Fluent in English (written and oral) Fluency in a second language is preferred.
• Comfortable working remotely with great communication skills for a remote work environment.

Bonus Qualifications

• Knowledge of any cloud. ( Especially Azure )