Senior Product Engineer

🧠 Job Description: Senior Java Developer (8+ Years Experience)

Location: Mumbai, India

Employment Type: Full-time, Hybrid mode of working

Company: Wissen Technology

Website: www.wissen.com

🚀 About Wissen Technology

Wissen Technology is a specialized technology consulting firm delivering cutting-edge solutions to global leaders in Banking & Finance, Telecom, and Healthcare. Established in 2015 and part of the Wissen Group (founded in 2000), Wissen has scaled rapidly with impressive impact and recognition.

• 🌍 Offices in US, UK, India, Australia, Mexico, and Canada
• 👥 1700+ Wissen Technology professionals; part of a 4500-strong Wissen Group
• 🏆 Great Place to Work® Certified
• 🧠 Featured as a Top 20 AI/ML Vendor (CIO Insider, 2020)
• 📈 Achieved 400% revenue growth in 5 years (with zero external funding)
• 💼 Delivered $1B+ worth of projects to 50+ Fortune 500 companies

Learn more about our work and thought leadership:

📄 Articles by Wissen | 💼 LinkedIn

About the Role

We are seeking an experienced Senior Java Developer with 8+ years of hands-on expertise in building scalable, high-performance applications. The ideal candidate will have strong fundamentals in Java, OOPS, Multithreading, Spring concepts, and SQL, and will play a key role in designing, developing, and optimizing enterprise-grade solutions.

Key Responsibilities

• Design, develop, and maintain complex applications using Core Java and Spring frameworks
• Apply advanced Object-Oriented Programming (OOPS) principles to deliver clean, modular, and reusable code
• Implement and optimize multithreaded applications for high-performance systems
• Work with SQL databases for efficient data modeling, query optimization, and integration
• Collaborate with cross-functional teams to gather requirements and translate them into technical solutions
• Conduct code reviews, troubleshoot issues, and ensure adherence to best practices
• Mentor junior developers and contribute to technical knowledge sharing within the team
• Ensure application scalability, performance tuning, and security compliance

Required Skills & Qualifications

• Bachelor’s/Master’s degree in Computer Science, Engineering, or related field
• 8+ years of professional experience in Java development
• Strong expertise in Core Java, OOPS, and Multithreading
• Hands-on experience with Spring concepts (Spring Core, Spring MVC, Spring Boot preferred)
• Proficiency in SQL and database design (MySQL, Oracle, PostgreSQL, etc.)
• Solid understanding of software development life cycle (SDLC) and Agile methodologies
• Strong analytical, problem-solving, and communication skills

🌟 Why Wissen?

Join a company that combines start-up agility with enterprise stability. Work alongside some of the brightest minds from institutions like MIT, Wharton, IITs, IIMs, and NITs. Be part of mission-critical projects for Fortune 500 giants, and grow in a culture that invests in your future.

We are seeking a motivated and detail-oriented Junior Backend Engineer to join our team. The role involves developing and maintaining backend systems using Django and Python, while also managing on-premises hardware and deployments. You will work closely with cross-functional teams to ensure our software is reliably configured, deployed, and maintained in an on-prem environment.

Key Responsibilities

Backend Development: Design, develop, and maintain backend services and APIs using Python (Django or Flask).

On-Prem Deployment: Install, configure, and manage software on on-premises hardware, including servers and networking equipment.

Database Management: Design database schemas, write efficient queries, and optimize data access layers (PostgreSQL, MySQL, etc.).

API Integration: Implement and maintain RESTful APIs and integrate with third-party services.

Troubleshooting & Debugging: Diagnose and resolve application and infrastructure issues to ensure high availability.

Version Control & CI/CD: Use Git for version control and contribute to continuous integration and delivery pipelines (GitHub Actions, Jenkins, etc.).

Security & Compliance: Work with the team to ensure software and infrastructure meet security and compliance requirements.

Documentation: Maintain clear, comprehensive documentation for your code, configurations, and on-prem deployment processes.

Requirements

• Extensive and expert programming experience in at least one general programming language (e. g.

Java, C, C++) & tech stack to write maintainable, scalable, unit-tested code.

• Experience with multi-threading and concurrency programming.

• Extensive experience in object oriented design skills, knowledge of design patterns, and a huge passion

and ability to design intuitive modules and class-level interfaces.

• Excellent coding skills - should be able to convert design into code fluently.

• Knowledge of Test Driven Development.

• Good understanding of databases (e. g. MySQL) and NoSQL (e. g. HBase, Elasticsearch, Aerospike etc).

• Strong desire to solve complex and interesting real world problems.

• Experience with full life cycle development in any programming language on a Linux platform.

• Go-getter attitude that reflects in energy and intent behind assigned tasks.

• Worked in a startup-like environment with high levels of ownership and commitment.

• BTech, MTech or Ph. D. in Computer Science or related technical discipline (or equivalent).

• Experience in building highly scalable business applications, which involve implementing large complex

business flows and dealing with huge amounts of data.

• 3+ years of experience in the art of writing code and solving problems on a large scale.

• Open communicator who shares thoughts and opinions frequently, listens intently, and takes

constructive feedback.

About the Role-

Thinking big and executing beyond what is expected. The challenges cut across algorithmic problem solving, systems engineering, machine learning and infrastructure at a massive scale.

Reason to Join-

An opportunity for innovators, problem solvers & learners.  Working will be Innovative, empowering, rewarding & fun. Amazing Office, competitive pay along with excellent benefits package.

Requiremets and Responsibilities- (please read carefully before applying)

• The overall experience of 3-6 years in Java/Python Framework and Machine Learning.
• Develop Web Services, REST, XSD, XML technologies, Java, Python, AWS, API.
• Experience on Elastic Search or SOLR or Lucene -Search Engine, Text Mining, Indexing.
• Experience in highly scalable tools like Kafka, Spark, Aerospike, etc.
• Hands on experience in Design, Architecture, Implementation, Performance & Scalability, and Distributed Systems.
• Design, implement, and deploy highly scalable and reliable systems.
• Troubleshoot Solr indexing process and querying engine.
• Bachelors or Masters in Computer Science from Tier 1 Institutions

• Degree in Computer Science (BS/MS), related technical field or equivalent practical experience
• 8+ years of industry experience in product development
• Experience in coaching and mentoring team members
• Must own a specific component of the product. Gathering requirements by working with product management. Working closely with development managers in defining external product interfaces
• Must have excellent written and verbal communication skills. Must articulate various design approaches and design decisions clearly - within the team and across the teams.
• Must work with QA engineers to devise proper test constructs - unit testing and integration tests.

• 5 years experience with the Django framework
• Experience with building APIs (REST or GraphQL) 
• Strong Troubleshooting and debugging skills
• React.js knowledge would be an added bonus 
• Understanding on how to use a database like Postgres (prefered choice), SQLite, MongoDB, MySQL.
• Sound knowledge of object-oriented design and analysis.
• A strong passion for writing simple, clean and efficient code.
• Proficient understanding of code versioning tools Git.

Experience:

• Min 5 year experience
• Startup experience is a must. 

Location:

• Remote developer

Timings:

• 40 hours a week but with 4 hours a day overlapping with client timezone.  Typically clients are in California PST Timezone.

Position:

• Full time/Direct
• We have great benefits such as PF, medical insurance, 12 annual company holidays, 12 PTO leaves per year, annual increments, Diwali bonus, spot bonuses and other incentives etc.
• We dont believe in locking in people with large notice periods.  You will stay here because you love the company.  We have only a 15 days notice period.

Java Developer Job Description

We are looking for a Java developer responsible for building Java applications.

Responsibilities

• Design, build and maintain efficient, reusable, and reliable Java code
• Identify bottlenecks and bugs, and devise solutions to these problems
• Help maintain code quality, organization, and automatization.

Skill Set:

• Proficient in Java, with a good knowledge of its ecosystems
• Java, Rest API integration, JSON, XML, Oracle, Microservices, Agile Scrum.
• Experience in developing large-scale distributed systems.
• API knowledge
• Solid understanding of object-oriented programming
• Familiar with various design and architectural patterns
• Skill for writing reusable Java libraries
• Spring, Spring Boot, Spring Cloud, React native
• Experience: 04 to 10 years
• Salary: As Per Market

Senior Software Engineer (Python)

Job description

Fulfil’s software engineers develop the next-generation technologies that change how millions of customer orders are fulfilled by merchants. Our products need to handle information at massive scale. We're looking for engineers who bring fresh ideas from all areas into our technology.

As a senior software engineer, you will work on our python based ORM and applications that scales to handle millions of transactions every hour. This is mission critical software and your primary focus will be building robust and scalable solutions that are easy to maintain.

In this role, you will be collaborating closely with the rest of the team working on different layers of infrastructure in an international environment. Therefore, a commitment to collaborative problem solving, sophisticated design, and quality product are important.

What You’ll Do:

• Own definition and implementation of API interfaces (REST and GraphQL). We take pride in our 100% open API with over 600 endpoints.
• Implement simple solutions to complex business logic that enables our merchants to manage financials, orders and shipments across millions of transactions.
• Build reusable components and packages for future use.
• Translate specs and user stories into reviewable, test covered patches.
• Peer review code and refactor existing code.
• Integrate with our eCommerce partners (Shopify, BigCommerce, Amazon), shipping partners (UPS, USPS, FedEx, DHL) and EDI.
• Manage Kubernetes and Docker based global deployment of our infrastructure.

Requirements

We’re Looking for Someone With:

• Experience working with ORMs like SQLAlchemy or Django
• Experience with SQL and databases (Postgres preferred)
• Experience in developing large server side applications and microservices
• Ability to create high quality code
• Experience with python testing tools (pytest) and test automation
• Familiarity with code versioning tools like GIT
• Strong sense of ownership and leadership quality
• Experienced in the tools of our web stack
• Python
• Celery
• Postgres
• Redis
• RabbitMQ

Nice to Haves:

• Prior experience at a growth stage Internet/Software company
• Experience with ReactJS, Google Cloud, Heroku
• Cloud deployment and scaling experience

About Us:

Fulfil.io helps high growth, high volume merchants simplify operations and scale for growth. With the rise in omni-channel commerce, Fulfil was founded with the simple idea that merchant operations need to be simplified in order to deliver amazing retail experiences. Fulfil enables businesses to turn their back office operations into an accelerator for growth by integrating order management, inventory management, warehouse management, vendor/supplier management, wholesale, manufacturing, financials and customer service, into one seamless solution. We believe merchants should love their operations platform, and we work hard to make that happen every single day. Fulfil.io is a trusted solution for brands like EndySleep, Mejuri, Lie-Nielson Toolworks, and many more.  

Fulfil.io is a venture backed technology company with offices in San Francisco, Toronto, and Bangalore. The team is made up of people who want to feel challenged at work, be the best at their craft and learn from one another. We come from different backgrounds and experiences, all passionate about the work we do, the team we do it with, and the customers we do it for. Join us in our journey to simplify operations and empower merchants around the world!