Java Backend Developer-Senior

Experience: 3 to 5

Location: Bangalore

Wissen Technology is now hiring for a Senior 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. - 3 to 5 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 Us:

At Wissen Technology, we deliver niche, custom-built products that solve complex business challenges across industries worldwide.

Founded in 2015, our core philosophy is built around a strong product engineering mindset—ensuring every solution is architected and delivered right the first time. Our commitment to excellence translates into delivering 2X impact compared to traditional service providers. How do we achieve this? Through a combination of deep domain knowledge, cutting-edge technology expertise, and a relentless focus on quality. 

We don’t just meet expectations—we exceed them by ensuring faster time-to-market, reduced rework, and greater alignment with client objectives. We have a proven track record of building mission-critical systems across industries, including financial services, healthcare, retail, manufacturing, and more. 

Wissen stands apart through its unique delivery models. Our outcome-based projects ensure predictable costs and timelines, while our agile pods provide clients the flexibility to adapt to their evolving business needs. Whether it’s AI/ML for unstructured data processing, cloud enablement, or data engineering, Wissen leverages its thought leadership and technology prowess to drive superior business outcomes. Our success is powered by top-tier talent. Our proprietary Interview Ninja platform ensures we hire the best, building high-performing teams that deliver unmatched results. 

Today, Wissen Technology has a global footprint with 2200+ employees across offices in the US, UK, UAE, India, and Australia. Our mission is clear: to be the partner of choice for building world-class custom products that deliver exceptional impact—the first time, every time.

Website : www.wissen.com 

About the Role:

We are seeking a skilled Java Developer to join our team. The ideal candidate will have strong experience in core Java development along with exposure to modern frameworks and tools. You will be responsible for designing, developing, and maintaining scalable applications while ensuring performance, security, and code quality.

Key Responsibilities:

• Design, develop, test, and maintain Java-based applications.
• Write clean, efficient, and reusable code following best practices.
• Collaborate with cross-functional teams (Product, QA, DevOps, etc.) to deliver high-quality software.
• Troubleshoot, debug, and optimize application performance.
• Participate in code reviews and contribute to continuous improvement.
• Stay updated with emerging trends, tools, and technologies in the Java ecosystem.

Required Skills & Qualifications:

• Strong proficiency in Core Java (Java 8/11/17).
• Experience with frameworks such as Spring / Spring Boot / Hibernate.
• Good knowledge of REST APIs, Microservices architecture.
• Familiarity with SQL/NoSQL databases (MySQL, PostgreSQL, MongoDB, etc.).
• Understanding of multithreading, collections, and design patterns.
• Experience with version control systems (Git) and build tools (Maven/Gradle).
• Solid problem-solving skills and ability to work in an Agile environment.

Good to Have:

• Exposure to cloud platforms (AWS, Azure, GCP).
• Knowledge of containerization (Docker, Kubernetes).
• Experience with messaging systems (Kafka, RabbitMQ).
• Familiarity with CI/CD pipelines.

JioTesseract, a digital arm of Reliance Industries, is India's leading and largest AR/VR organization with the mission to democratize mixed reality for India and the world. We make products at the cross of hardware, software, content and services with focus on making India the leader in spatial computing. We specialize in creating solutions in AR, VR and AI, with some of our notable products such as JioGlass, JioDive, 360 Streaming, Metaverse, AR/VR headsets for consumers and enterprise space.

Mon-Fri, In office role with excellent perks and benefits!

Key Responsibilities:

1. Design, develop, and maintain backend services and APIs using Node.js or Python, or Java.

2. Build and implement scalable and robust microservices and integrate API gateways.

3. Develop and optimize NoSQL database structures and queries (e.g., MongoDB, DynamoDB).

4. Implement real-time data pipelines using Kafka.

5. Collaborate with front-end developers to ensure seamless integration of backend services.

6. Write clean, reusable, and efficient code following best practices, including design patterns.

7. Troubleshoot, debug, and enhance existing systems for improved performance.

Mandatory Skills:

1. Proficiency in at least one backend technology: Node.js or Python, or Java.

2. Strong experience in:

i. Microservices architecture,

ii. API gateways,

iii. NoSQL databases (e.g., MongoDB, DynamoDB),

iv. Kafka

v. Data structures (e.g., arrays, linked lists, trees).

3. Frameworks:

i. If Java : Spring framework for backend development.

ii. If Python: FastAPI/Django frameworks for AI applications.

iii. If Node: Express.js for Node.js development.

Good to Have Skills:

1. Experience with Kubernetes for container orchestration.

2. Familiarity with in-memory databases like Redis or Memcached.

3. Frontend skills: Basic knowledge of HTML, CSS, JavaScript, or frameworks like React.js.

About Quantela

We are a technology company that offers outcomes business models. We empower our customers with the right digital infrastructure to deliver greater economic, social, and environmental outcomes for their constituents.

When the company was founded in 2015, we specialized in smart cities technology alone. Today, working with cities and towns; utilities, and public venues, our team of 280+ experts offer a vast array of outcomes business models through technologies like digital advertising, smart lighting, smart traffic, and digitized citizen services.

We pride ourselves on our agility, innovation, and passion to use technology for a higher purpose. Unlike other technology companies, we tailor our offerings (what we can digitize) and the business model (how we partner with our customer to deliver that digitization) to drive measurable impact where our customers need it most. Over the last several months alone, we have served customers to deliver outcomes like increased medical response times to save lives; reduced traffic congestion to keep cities moving and created new revenue streams to tackle societal issues like homelessness.

We are headquartered in Billerica, Massachusetts in the United States with offices across Europe, and Asia.

The company has been recognized with the World Economic Forum’s ‘Technology Pioneers’ award in 2019 and CRN’s IoT Innovation Award in 2020.

For latest news and updates please visit us at www.quantela.com

Overview of the Role

Collaborate with cross-functional teams to define, design and build performant modern web applications and services. Build high quality web applications and services by writing clean and modular code

Must have Skills

• 10+ years of experience in leading teams and delivering product, write unit and integration tests to ensure robustness and reliability of web applications and services. 
• Measure and improve performance of microservices.
• Catalyze growth within the team through code reviews and pair programming to maintain high development standards Investigate operational issues to find the root cause and propose improvements Design, build, and maintain APIs, services, and systems across Stripe’s engineering teams.
• Expert level of experience in design and development of Web Applications, highly scalable distributed systems.
• Should have experience in development skills using latest technologies including NodeJS, Microservices, Elastic search, Timescale DB, Kafka, Redis, etc.
• Should have exposure in NoSQL and SQL development.
• Comprehensive knowledge of physical and logical data modelling, performance tuning.
• Should possess excellent communication, presentation, and interpersonal skills.
• Ability to work collaboratively and productively with globally dispersed teams
• Build high performance teams and Coach team for successful career growth
• Experience working with relational and non-relational databases, query optimization, and designing schema

Desired Background

Bachelors/Masters degree in Computer Science or Computer Applications

Knowledge & Experience required:

·        Bachelor's degree in Computer Science Engineering or equivalent degree.

·        7 years of development experience as a seasoned Java developer

·        7 years of experience in developing enterprise applications using enterprise Java 8 and has worked both on Web and Server side technologies.

·        A strong Java Backend Developer with Core Java 8, Spring, Spring Boot, Hibernate, REST Web-services.

·        Expertise in Java Unit Testing Frameworks and tools such as JUnit, TestNG, Mockito etc.

·        As a Senior developer, must be comfortable switching tasks between Web Services, APIs, Batch Job engine or Web Development.

·        Passionate Java developer who is also a problem solver and has a very good understanding of core and advanced Java concepts.

·        Good understanding of database and data fundamentals in SQL Server 2017, Oracle and NoSql databases.

·        Good understanding of Web Service concepts and experience building RESTful services is required.

We're on a mission to make it possible for every person, team, and company to be able to tailor their software to solve any problem and take on any challenge. Computers may be our most powerful tools, but most of us can't build or modify the software we use on them every day. At Notion, we want to change this with focus, design, and craft.

We've been working on this together since 2016, and have customers like Pixar, Mitsubishi, Figma, Plaid, Match Group, and thousands more on this journey with us. Today, we're growing fast and excited for new teammates to join us who are the best at what they do. We're passionate about building a company as diverse and creative as the millions of people Notion reaches worldwide.

Millions of people use Notion — and this number is increasing every day. That means a million people trust us to deliver a fast, reliable, and secure experience, and we value this more than anything. We want to keep earning trust, while also continuing to amaze our users with the tools they can build in Notion. This is where you come in — to help us forge a performant and reliable path forward to the future.

• Write clean, secure, tested, and documented code.
• Design & enhance the Notion platform with new capabilities, as and when the need arises.
• Contribute to monitoring & scaling the architecture of the platform and the infrastructure.
• Write technical documentation, and contribute to determining internal processes.
• Contribute to recruiting of new backend employees

• 6+ years of experience building scalable platforms. 
• Good understanding of database (Relational Or Nosql) internals like transactions, indexes. Experience in schema design.
• 2+ years of experience working on the AWS platform, and acquaintance with technologies like Elastic Beanstalk, AWS Lambda, Elastic Load Balancer.
• Good understanding of docker internals.
• Good communication skills, good leadership skills, attention to detail, a sound understanding of algorithms, and object-oriented programming.

• You're proficient with any part of our technology stack: React, TypeScript, Node.js, Memcached, Postgres, Docker, and Elasticsearch.
• You've heard of computing pioneers like Ada Lovelace, Douglas Engelbart, Alan Kay, and others—and understand why we're big fans of their work.
• You have interests outside of technology, such as in art, history, or social sciences.

Our customers come from all walks of life and so do we. We hire great people from a wide variety of backgrounds, not just because it's the right thing to do, but because it makes our company stronger. If you share our values and our enthusiasm for small businesses, you will find a home at Notion.

Notion is proud to be an equal opportunity employer. We do not discriminate in hiring or any employment decision based on race, color, religion, national origin, age, sex (including pregnancy, childbirth, or related medical conditions), marital status, ancestry, physical or mental disability, genetic information, veteran status, gender identity or expression, sexual orientation, or other applicable legally protected characteristic. Notion considers qualified applicants with criminal histories, consistent with applicable federal, state and local law. Notion is also committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If you need assistance or an accommodation made due to a disability, please let your recruiter know.

Experience:

The candidate should have about 5+ years of experience with design and development in Java/Scala. Experience in algorithm, data-structure, database and architectures of distributed System is mandatory.

Required Skills:

1. In-depth knowledge of Hadoop, Spark architecture and its components such as HDFS, YARN and executor, cores and memory param
2. Knowledge of Scala and Java both
3. Extensive experience in developing spark job. Should possess good Oops knowledge and be aware of enterprise application design patterns.
4. Good knowledge of Unix/Linux.
5. Experience working on large-scale software projects
6. Understanding the big picture and the various uses cases involved while crafting the solution and documenting them in Unified Modeling language.
7. Own and maintain the architecture document.
8. Keep an eye out for technological trends, open-source projects that can be used.
9. Knows common programming languages and Frameworks.
10. Real time streaming data consumption

Good to have :

1. Azure/AWS Cloud Knowledge of Data Storage and Compute side
2. Knowledge Multitenant Architecture
3. Brief idea of Data Science
   
   

Requirements :

- 3+ years of professional software development experience

- 2+ years of object-oriented Java/J2EE hands-on development

- Spring (MVC, IOP/DI, REST, Security) & Hibernate/Spring

- REST web services

- Anyone of the messaging solutions like Kafka, RabbitMQ

Desirables :

- SQL, No SQL concepts

- Experience of Redis or/and Mongo DB

- Agile methodology

- Experience leading or working with cross geography teams

- Unix, shell scripting & Build Systems

Bonus :

- Microservice design and development experience

- Android application development experience

- Experience in performance optimization is an added advantage

- Full SDLC experience (requirements gathering, architecture, development, QA, etc.)

Responsibilities :

- You will be working with the Supply Chain Management team building a leading eCommerce platform for Asian markets

- Order Promising system, promising the order delivery promise date to customer by applying the constraints on current resource availability across different steps in the supply chain. This system needs to scale for thousands of requests per minute with few million seconds of response time

- Warehouse and Inventory Management system, this system needs to scale to processing huge number of orders across different warehouse.

- Transportation and Logistics Management, involves planning and delivery of huge number orders to end customer. This system has the workflows to manage first mile, line haul and last mile delivery to customer

- Inventory Planning, helps in tracking different selling behaviours of the items and triggers / helps planners to replenish, promote, markdown or place inventory at right place to cut down the on hand inventory requirements

- You will be actively involved during the entire technology development lifecycle. Responsibilities will include all aspects from design, coding review, coding, unit testing, end user feedback cycle changes and manging and scaling the system in production.

- Primary role in leading software development teams

- The customized solutions that you will be architecting and developing will also require knowledge and experience with spring / Hibernate, SOAP / REST, microservices and SQL.

- Ability to learn new technologies quickly and willingness to read and digest large existing source code and take ownership on complex component or subsystem to drive improvements and re-architecture

- Work with a team of amazing developers and designers involved in the design and development of global platforms

- Invent and prototype new features, build, test and ship them to customers as SaaS, cloud-based or hosted product platforms

- Drive the implementation of new technologies that improve our ability to build great customers products.

- Participate in a fun, open learning environment with great benefits and smart talented folks that represent among the best globally.

Qualification :