Java Full stack Developer

Job Title : React + Node.js Developer (Full Stack)

Experience : 5+ Years

Location : Mumbai or Pune (Final location to be decided post-interview)

Notice Period : Immediate to 15 Days

Interview Rounds : 1 Internal Round + 1 Client Round

Job Summary :

We are looking for a highly skilled Full Stack Developer (React + Node.js) with strong expertise in both frontend and backend development.

The ideal candidate should demonstrate hands-on experience with databases, excellent project understanding, and the ability to deliver scalable, high-performance applications in production environments.

Mandatory Skills :

React.js, Node.js, PostgreSQL/MySQL, JavaScript (ES6+), Docker, AWS/GCP, full-stack development, production system experience, and strong project understanding with hands-on database expertise.

Key Responsibilities :

• Design, develop, and deploy robust full-stack applications using React (frontend) and Node.js (backend).
• Exhibit a deep understanding of database design, optimization, and integration using PostgreSQL or MySQL.
• Translate project requirements into efficient, maintainable, and scalable technical solutions.
• Build clean, modular, and reusable components following SOLID principles and industry best practices.
• Manage backend services, APIs, and data-driven functionalities for large-scale applications.
• Work closely with product and engineering teams to ensure smooth end-to-end project delivery.
• Use Docker and cloud platforms (AWS/GCP) for containerization, deployment, and scaling of services.
• Participate in design discussions, code reviews, and troubleshooting production issues.

Required Skills :

• 5+ Years of hands-on experience in full-stack development using React and Node.js.
• Strong understanding and hands-on expertise with relational databases (PostgreSQL/MySQL).
• Solid grasp of JavaScript (ES6+), and proficiency in Object-Oriented Programming (OOP) or Functional Programming (FP).
• Proven experience working with production-grade systems and scalable architectures.
• Proficiency with Docker, API development, and cloud services (preferably AWS or GCP).
• Excellent project understanding, problem-solving ability, and strong communication skills (verbal and written).

Good to Have :

• Experience in Golang or Elixir for backend development.
• Knowledge of Kubernetes, Redis, RabbitMQ, or similar distributed tools.
• Exposure to AI APIs and tools.
• Contributions to open-source projects.

Fountane Archipelago  ·  Island Role

A Little Bit About the Role

We are looking for a Senior Product Engineer (L3) who thrives in complexity. Most engineers build on blank canvases — you build on someone else’s mess and leave it better than you found it.

The majority of your work at L3 will be on existing, live codebases — disorganised, partially documented, built by multiple teams over multiple years. Your job is to enter those systems, understand them before touching them, extend and clean them without breaking what works, and progressively bring them up to a standard where AI tooling can accelerate further development. This is the core of what L3 does at Fountane. If you have only built greenfield projects, this role will be hard.

You are expected to be genuinely full stack: comfortable owning web applications and mobile apps, the frontend, backend, database, state management, and API integration layer — without needing to hand off to a specialist.

You will work closely with the Concept Engineer on your Island — translating their prototypes into production architecture, raising technical blockers early, and keeping the sprint honest. You will also review code, mentor junior engineers, respond to production incidents, and contribute to the network’s shared knowledge base.

All of this is done primarily with Cursor and Claude as your execution and reasoning tools. AI-assisted engineering is not a feature of this role — it is the method.

AI-First Engineering Expectation

Cursor and Claude are your primary tools — not supplements. Engineers at L3 who are not using AI at the codebase level are not operating at this level.

At L3, AI-assisted engineering means:

• Loading full codebase context into Cursor before writing a single line — understanding the system before touching it.
• Writing scoped, precise refactor prompts that isolate changes to one concern at a time.
• Using Cursor to generate tests that document existing behaviour before any restructuring begins.
• Using Claude for architecture reasoning, decision documentation, and translating CE briefs into structured technical plans.
• Producing inline documentation and decision records as part of the AI-assisted workflow — not as an afterthought.
• Sharing effective prompt patterns and Cursor discoveries with the broader Fountane network — kept to yourself, they are a missed contribution.

Key Responsibilities

Legacy Codebase Refactoring & the Cleaning Phase

This is the primary L3 engagement type at Fountane. You will be handed existing, partially documented codebases — built by previous teams, often without tests, with inconsistent patterns — and your job is to refactor them into a clean, AI-promptable state without losing existing functionality. You use Cursor’s codebase context window to navigate safely, write characterisation tests before touching anything, and make changes in small, reviewable increments. The standard is: every module you leave should be easier to extend by AI tooling than when you found it.

Full Stack Development — Web & Mobile

Build and own the full application layer: React / Next.js web frontends, React Native or Flutter mobile apps, Node.js / Python backends, and relational and non-relational databases. You should be able to pick up web or mobile on any engagement without needing a handoff. Schema design, data modelling, and state architecture are yours to own — including diagnosing and fixing broken or leaking state in existing frontends.

Third-Party API Integrations

Integrate complex third-party services — payments (Stripe), communications (Twilio), auth (Auth0), and others — reliably and without creating brittle dependencies. Own the integration layer end to end: error handling, retries, failure modes, and documentation. If a third-party integration is flaky in production, that is your problem to own.

CE Collaboration & Sprint Integrity

Work directly with the Concept Engineer to translate prototypes into buildable technical plans. Review CE briefs before the sprint starts — if the scope is technically unrealistic, the time to say so is before work begins, not on demo day. Raise blockers against acceptance criteria proactively. You are the technical check on what the CE promises the client.

Security Awareness

Write code that does not require the Lead to security-audit every line. This means: input validation by default, no hardcoded secrets, correct auth scoping, safe handling of user data, and awareness of common vulnerabilities (injection, broken auth, insecure direct object references) in the context of the stacks you work in. You are not the security architect — the Lead owns that — but you are expected to produce code that does not introduce obvious vulnerabilities.

Production Incident Response

When something breaks in production, you are on it. Diagnose the issue, apply a safe fix or rollback, document what happened and why, and hand a clear summary to the Lead for the client post-mortem. Speed matters, but a bad fix that causes a second incident is worse than a slow fix that is correct. Response expectation: acknowledged within 1 hour, resolved or escalated with a clear status within 4 hours.

Codebase Navigation & Safe Refactoring

On all engagements — not just Cleaning Phase work — keep changes small, focused, and reviewable. One type of change per commit. Write tests that document existing behaviour before restructuring. Leave every module easier to understand than when you found it.

Code Review

Review pull requests from L1 and L2 engineers with specific, actionable feedback — not rubber-stamp approvals. A good code review at L3 leaves the author understanding what to do differently next time, not just what to fix now. Review weekly; do not let PRs age.

Mentoring

Review junior engineers’ code weekly with specific, useful feedback — this is distinct from quality-gate code review. The goal here is teaching, not gatekeeping. Run monthly pairing sessions to help them grow. The measure of good mentoring is whether they are becoming more capable and less dependent on you over time.

Documentation

Write short decision records when you make significant technical choices. Leave every module you touch easier to understand than when you found it. Treat documentation as part of the engineering work, not a separate task you do at the end.

Qualifications

• 5+ years of experience as a software engineer, with a strong track record on real production codebases you did not build from scratch — incomplete documentation, inconsistent patterns, other people’s decisions. If your experience is primarily greenfield, this role will be a difficult fit.
• Genuinely full stack across web and mobile: proficient in React / Next.js and at least one of React Native or Flutter, Node.js or Python on the backend, and comfortable with both relational and non-relational databases including schema design.
• Hands-on, daily Cursor and Claude usage at the codebase level. You should be able to describe concretely how you use AI in your engineering workflow — not in general terms.
• Experience integrating complex third-party APIs in production environments — not just following a quickstart guide. You should be able to describe an integration that failed in production and what you did about it.
• Solid security awareness for the stacks you work in: input validation, auth scoping, safe data handling. You do not need a security specialism, but you should not be writing code that introduces obvious vulnerabilities.
• Has conducted meaningful code reviews that improved the code and the author, not just approved the PR.
• Has coached or mentored junior engineers before, and done it well.
• Comfortable with production incident response — diagnosing issues under pressure, applying safe fixes, and communicating clearly to a Lead or client about what happened.
• Treats documentation as part of the job, not an afterthought.
• Bachelor’s or Master’s in Computer Science or a related field, or equivalent experience.

About Fountane

Fountane is a technology ventures lab - one part product studio, one part startup engine. We build high-quality software and AI products for clients ranging from fast-moving startups to large enterprises, and we co-build and invest in new companies when we see the right opportunity.

Founded in 2017 and headquartered in Minneapolis, we have grown to 60+ people across four continents and were recognised as one of America’s fastest-growing companies, ranking No. 699 on the Inc. 5000 with 595% three-year growth.

We are radically open-minded, serious about craft, and direct about expectations. If you want to do meaningful work without politics, this is the place.

Company: Billion-dollar US-based Retail

About the Role:

We are seeking a talented and experienced Fullstack Engineer with a strong focus on frontend development to join our dynamic team. You will work with modern web technologies to design and implement highly scalable and user-friendly interfaces for our global e-commerce platform. This is a hybrid role requiring 3 days a week from the office and 2 days remote.

Key Responsibilities:

Develop and maintain high-performance web applications with a primary focus on frontend features.

Collaborate with designers, backend engineers, and product managers to deliver seamless user experiences.

Write clean, maintainable, and scalable code using React.js, Vue.js, and other modern frameworks.

Integrate and optimize backend services using Node.js and PostgreSQL.

Participate in code reviews, mentoring sessions, and team discussions to uphold engineering excellence.

Stay up-to-date with emerging trends and technologies in fullstack and frontend development.

Required Skills and Experience:

8+ years of professional experience in software development, focusing on fullstack engineering.

Strong proficiency in React.js and/or Vue.js for frontend development.

Solid understanding of Node.js for backend services.

Experience with relational databases like PostgreSQL.

Proficiency in building responsive, cross-browser-compatible, and accessible user interfaces.

Familiarity with agile development methodologies and version control systems like Git.

Excellent problem-solving skills and the ability to work effectively in a team-oriented environment.

Preferred Qualifications:

Previous experience in the retail/ E-commerce / and finance domain a plus.

• 5 to 8 years ‘Hands-on’ experience in Java/J2EE/Microservices development
• Hands on with CODING in both JAVA and Angular 2+
• Experience constructing custom Microservices applications using Java, SpringBoot, Spring Cloud and Spring Core.
• Experience in Spring boot 4 or more years.
• Last job to be completely hands on in Spring Boot and looking for hands on in Spring Boot the next role.
• Experience in writing unit test cases (JUnit)
• Well used to Agile (XP, Scrum, SAFe)
• REST Services (HTTP methods, CRUD, Status codes, Authentication, Authorisation)
• Angular 2+, HTML,CSS

Full Stack Developer responsible for managing back-end services and the interchange of data between the server and the users.

Your primary focus will be the development of all server side logic, definition and maintenance of the central database, and ensuring high performance and responsiveness to requests from the front-end. You will also be responsible for integrating the frontend elements built by your co-workers into the application. Therefore, a basic understanding of frontend technologies is necessary as well.

We are looking to recruit a candidate for a role that will require:

• Create and consume restful APIs
• Design, develop, and maintain internal and external applications
• Build efficient, testable, and reusable modules
• Write high quality, structured application/interface code and documentation
• Identify solutions through research and collaboration that resolves the root of problems as they arise
• Define functional and technical requirements for application software to develop skills and knowledge
• Troubleshoot, test and maintain the core product software and databases to ensure strong optimization and functionality
• Contribute in all phases of the development lifecycle

Requirement

∙ Proficient in Node.JS and ReactJS development stack

∙ 2+ years’ experience designing, querying, and updating databases in MySQL/nosql

∙ Basic understanding of web technologies including HTML, CSS, JavaScript, AJAX etc.

∙ Passion for best design and coding practices and a desire to develop new bold ideas

∙ Good to have knowledge of AWS, Redis, ElasticSearch

Education: Min. Graduate in related discipline

Work experience: 2 years relevant experience

Note: We are looking for real, hands-on experience—not certifications or copy-paste portfolios. Selected candidates will be given a short real-world task to evaluate skills before interview.

Key Responsibilities

• Design, build, and maintain scalable full-stack applications using MongoDB, Postgresql, Express.js, React.js, and Node.js
• Develop RESTful APIs and integrate them with frontend systems
• Collaborate with designers and project managers for timely project delivery
• Optimize code for performance and scalability
• Troubleshoot, debug, and upgrade applications as needed
• Follow Git-based workflows for version control

Must-Have Skills

• Strong hands-on experience in:
• React.js with hooks, context API, component architecture
• Node.js with Express.js
• MongoDB (CRUD operations, schema design) & Postgresql
• API development and integration
• Strong JavaScript fundamentals (ES6+)
• Basic understanding of deployment (e.g., cPanel, Vercel, Heroku, or VPS)
• Git and GitHub for code versioning

Good-to-Have Skills

• Knowledge of Redux or any other state management tools
• Experience with Next.js or TypeScript
• Familiarity with Tailwind CSS or Material UI
• Experience integrating third-party APIs (e.g., payment gateways, social logins)

Who Should Apply

• You’ve worked on real client projects or have built and shipped working applications.
• You are disciplined and take ownership without constant follow-up.
• You are not here to "fake it till you make it"—you’re here to grow with a real team.