Java API Developer

Company Name – Wissen Technology

Group of companies in India – Wissen Technology & Wissen Infotech

Work Location - Senior Backend Developer – Java (with Python Exposure)- Mumbai

Experience - 4 to 10 years

Kindly revert over mail if you are interested.

Java Developer – Job Description

We are seeking a Senior Backend Developer with strong expertise in Java (Spring Boot) and working knowledge of Python. In this role, Java will be your primary development language, with Python used for scripting, automation, or selected service modules. You’ll be part of a collaborative backend team building scalable and high-performance systems.

Key Responsibilities

• Design and develop robust backend services and APIs primarily using Java (Spring Boot)
• Contribute to Python-based components where needed for automation, scripting, or lightweight services
• Build, integrate, and optimize RESTful APIs and microservices
• Work with relational and NoSQL databases
• Write unit and integration tests (JUnit, PyTest)
• Collaborate closely with DevOps, QA, and product teams
• Participate in architecture reviews and design discussions
• Help maintain code quality, organization, and automation

Required Skills & Qualifications

• 4 to 10 years of hands-on Java development experience
• Strong experience with Spring Boot, JPA/Hibernate, and REST APIs
• At least 1–2 years of hands-on experience with Python (e.g., for scripting, automation, or small services)
• Familiarity with Python frameworks like Flask or FastAPI is a plus
• Experience with SQL/NoSQL databases (e.g., PostgreSQL, MongoDB)
• Good understanding of OOP, design patterns, and software engineering best practices
• Familiarity with Docker, Git, and CI/CD pipelines

Requirements

• Senior SD4 engineer/Principal Engineer/ Architect who has led or been part of platform teams inside a large/mid tech company
• Deep expertise working with any of the programming languages to write maintainable, scalable, unit-tested code.Python experience is a bonus - but not required
• Good understanding of REST APIs and the web in general and ability to build a feature from scratch & drive it to completion
• Experience with Kubernetes, Prometheus, Grafana, ELK stack, Load Balancing
• Experience in building a platform team on AWS for Product based companies/start-ups

What You’ll Do

• Build the core technology platform, including Automated provisioning of infrastructure, deployment, and monitoring of services
• Build a central services directory within an organization that shows the cost and health of all services and makes the management of microservices extremely easy
• This involves working with core infrastructure and understanding them in great detail - like Kubernetes, ServiceMesh, Service security
• Mentor/coach engineers to facilitate their development and provide technical leadership

• Strong experience in Java programming.
• Must have experience on MicroServices using Spring boots /Jersy /Swagger / any other Microservices technology stack
• Good experience in either Spring or Hibernate
• Must have at least 1to 2 years’ experience in Web application
• Knowledge of OOP concepts, industry best practices, and design
• Good understanding of web technology/enterprise-level applications
• Good to have experience in JavaScript frameworks
• Good to have experience in Agile Methodology

• Self-motivated and a Quick Learner
• Creative ideas with a problem-solving mindset.
• Ability to consistently perform and meet deadlines
• Attention to detail and follow-through
• A good understanding of customer satisfaction
• Ability to work effectively in a team as well as in an individual environment
• Excellent written and verbal communication skills

Responsibilities

- Software Engineering

- Design and develop highly scalable, available, reliable, secure and fault tolerant systems with minimal

guidance for a market leader in the logistics industry

- Partner with team members on functional and nonfunctional requirements and spread design

philosophy, goals and improve the code quality across the team

- Research new technologies and tools that enable building the next generation of our services

- Provide technology leadership to the team and foster engineering excellence

- Product Delivery

- Partner with product managers to define and execute on the feature roadmap

- Translate business requirements into scalable and extensible design

- Coordinate with various cross functional teams on planning and execution

- Maintaining automated build / test / deployment environments

Qualifications

- Software Engineering

- Should have at least 4 years of hands on experience in designing, developing, testing and deploying

applications on Java, Ruby, Kotlin, Python, Node or Go for large scale applications

- Deep knowledge of one of the programming language they have experience in

- Proficient in OOP and Design Patterns, experience with functional programming would be a plus

- Data modelling experience in Relational Databases

- Ability to design and implement low latency RESTful services

- Product Delivery

- Ability to scope, review and refine user stories for technical completeness and to alleviate dependency

risks.

- Well versed in working with agile methodologies which includes phases such as design, development,

code review, testing and release management

- Ability to have worked in a CI/CD environment, with hands on experience with Git or any similar source

code management tools

- Product Maintenance

- Experience troubleshooting server performance issues such as memory tuning, GC tuning, resource leaks

etc

- Continuously refactor applications to ensure high quality design.

Must-Have:

• Core Java (Must be good in Core Java concepts, Java programming practices, Clean coding.)
• Spring Framework(Must have working experience in Spring Core)
• Any SQL framework(hands-on working experience in any of these: Hibernate/JPA/MyBatis/Spring Data/Others)
• Hands-on experience in REST API
• Hands-on experienceSQL Database(any of the databases: Oracle/MySQL/PostgreSQL/SQLServer)
• Must have working experience with basic GIT
• Maven or Gradle (Must have working experience in building Java projects using maven or Gradle.)
• Should be able to work independently under someone's guidance.

Good to have:

• Advanced Java(Threading, Performance optimization)
• Spring Boot
• Other Spring frameworks(Spring Security, Spring Batch, Others)
• Microservices - Any NoSQL database(MongoDB, Cassandra, others)
• Application designing concepts.

Are you passionate about using technology to make people's lives better? Are you interested in becoming a part of one of the hottest trends in the world of start-ups today? Are you excited about joining the online ultra-fast grocery delivery service business pioneer and driving the trend forward? Then this may be the right opportunity for you.

Role and Responsibilities

1. Helping lead the software development lifecycle: technical design, implementation, testing, deployment, and support.
2. Working with cross-functional teams effectively to enable business growth.
3. Proactively identifying engineering bottlenecks and initiating proposals to improve them.
4. Writing high-quality, well-tested code in alignment with industry-wide best practices.
5. Applying a product mindset to back-end systems.
6. 1.  

1. About five years of experience delivering product-quality code in an agile set-up
2. Experience with Golang, REST APIs, Microservice Architecture, Elasticsearch, Redis, Docker, or Kubernetes
3. Understanding of the philosophy of cloud and an experience of maintaining cloud-native services.
4. Experience in designing, building, scaling, and maintaining production services, and knowledge of composing a service-oriented architecture.
5. Experience of working in a fast-paced, rapidly-growing company (Good to Have).
6. Working knowledge of Node.js (Good to Have).
7. 1.  

1. Passionate about technology and making an impact.
2. A perpetual learner, who stretches their boundaries and enjoys new ideas.
3. A doer who takes initiative and works well in a team.
4. 1.  

Who We Are

Blok is a technology-first, online ultra-fast grocery delivery service business, and we are on our way to revolutionize how millions of people across countries consume groceries. We believe in a world where getting everything you need, when you need it, sustainably, is the new normal. And it takes less than 10 minutes.

We believe we are positioned to lead this revolution. Why? Our founding and early team has held senior positions at Deliveroo, Uber, Glovo, Mercadona, or Unilever. We have done this before, and we believe we can do it again. But this time, even better.

Embark on the journey and help us launch the revolution in one of the highest growth industries of the year. Help us shape the new normal.