Fullstack Developer

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.

🚀 Hiring: MERN Stack Developer

⭐ Experience: 3+ Years

📍 Location: Mumbai ( Andheri East)

⭐ Work Mode:- 5 Days Work From Office

⏱️ Notice Period: Immediate Joiners

(Only immediate joiners & candidates serving notice period)

We are looking for a MERN Stack Developer skilled in MongoDB, Express.js, React.js, and Node.js to build scalable, high-performing web applications.

💫 What We’re Looking For:

✅ Proficiency in React.js, Node.js, Express.js, MongoDB

✅Strong in JavaScript (ES6+), REST APIs, Git

✅Good problem-solving & debugging skills

Designing, building, and automating ETL processes using AWS services like Apache Sqoop, AWS S3, AWS CLI, Amazon 

EMR, Amazon MSK, Amazon Sagemaker. 

∙Developing and maintaining data pipelines to move and transform data from diverse sources into data warehouses or 

data lakes. 

∙Ensuring data quality and integrity through validation, cleansing, and monitoring ETL processes. 

∙Optimizing ETL workflows for performance, scalability, and cost efficiency within the AWS environment. 

∙Troubleshooting and resolving issues related to data processing and ETL workflows. 

∙Implementing and maintaining security measures and compliance standards for data pipelines and infrastructure. 

∙Documenting ETL processes, data mappings, and system architecture. 

We're seeking a talented and motivated Full Stack Developer who is experienced in Node.js, React.js, and Laravel (PHP) to work on building high-performance web applications, APIs, SaaS platforms, and hosting tools. This role is perfect for someone who thrives in a dynamic environment and wants to contribute to modern, scalable platforms used by thousands of users.

Responsibilities

Develop and maintain full-stack applications using Node.js (backend), React.js (frontend), and Laravel (backend).

Design, implement, and document APIs and microservices for internal and customer-facing platforms.

Integrate third-party APIs, payment gateways, and other services as needed.

Collaborate with UI/UX designers to ensure a high-quality user experience.

Optimize applications for maximum speed and scalability.

Troubleshoot, debug, and upgrade existing software.

Participate in code reviews, sprint planning, and team meetings.

Roles and Responsibilities
1. Ability to work on diverse backend stack such as Node JS, Express JS
2. Ability to work on diverse frontend stack such as Meteor JS, React JS, HTML5, CSS3

3. Ability to deliver quick POC’s using cutting edge technologies.

4. Preparing reports, manuals and other documentation on the status, operation and maintenance of software.

5. Design, develop, and unit test applications in accordance with established standards

6. Developing, refining, and tuning integrations between applications. Analyzing and resolving technical and application problems.

7. Ability to debug the application.

8. Should have complete knowledge of developing RESTful Services.

9. Should be able to also work in agile development methodology.
10. Work with designated JavaScript framework to design, develop, and debug web applications
11. Work with the team to manage, optimize, and customize multiple web applications
12. Manage end to end module lifecycle management of the product
13. Push and pull codes via Git repository

Competency Requirements

1. Experience in NodeJS and development using MeteroJS
2. Experience in front end frameworks - Meteor JS
3. Experience in client/server application development
4. Knowledge of agile development methodologies
5. Knowledge of unit testing theory
6. Knowledge of AWS cloud
7. Knowledge of other frontend frameworks like ReactJS, AngularJS will be an advantage

We are looking for Sr. Node Js Developer

Experience - 1-5 years 

Location - Ahmedabad, Gujarat. (Work from Office/Home)

5 Days working 

Should have good communication skills.

Requirements:

•API Development

• Mongodb or Firebase

•Designing and developing user interfaces using Angular OR JavaScript MV-VM/MVC frameworks

•Good understanding of AJAX and JavaScript, TypeScript Dom manipulation Techniques

•Experience with RESTful services

•Expert in any one of the modern JavaScript MV-VM/MVC frameworks (AngularJS, JQuery, ReactJS)

•Knowledge of Node.js, Express and frameworks available for it

•Understanding the nature of asynchronous programming and its quirks and workarounds

•User authentication and authorization between multiple systems, servers, and environments


Note:- We are not providing permanent work from home. They have to come to the office if needed.

Who should not apply for this job

• If you are looking for a 100% hike in your salary but can't commit to what value you will bring on the table
• If you never read books
• If you jump companies every 11-12 months
• If you are not comfortable working on Saturdays
• If you have less than 2 years of experience
• If you have more than 4 years of experience

At this position you will:

• Get solid experience with high-load distributed architecture using REST and High load services.
• Work with automated CI/CD processes, AWS cloud, and VoIP.
• Implement and support microservices based on Elasticsearch, Mongo, and frontend.

Key-Skills Required:

Node.js  | Express  | REST Api   | Javascript  | Redux-Saga |   MongoDB | Web security TLS/SSL | Web Sockets |   Promises & Call-backs | Database & Data structures |   Redis | Elasticseach | React.Js

Key Deliverables: 

• New feature design and implementation, Bug fixing, testing and performance tuning.
• Work on the API and Engines.
• Code deployment on cloud & maintenance of the same.
• Take complete ownership of a product/feature from setup to deployment.
• Time-bound feature delivery & updating.
• Cost-saving using efficient & effective technologies

Role and Responsibilities: 

• Work on back-end (+ frontend integration) development of core scripts using NodeJS / MongoDB /Express /Redux, and Redis.
• Manage Key-value based databases like Redis.
• Active participation in the development of a sophisticated platform as one of the leading developers.
• Document code consistently throughout the development process by listing a description of the program, special instructions, and any changes made in database tables on procedural, modular, and database level.
• Respond promptly and professionally to bug reports. 
• Knowledge of bluebird.js (Promises), Async, etc will be of advantage.
• Coding and programming using Object-Oriented Programming, Data Structure and Algorithms, architecture/ design and build RESTful API.
• Passionate about building products and features and build the product from scratch with thrust on Web security, TLS/SSL, web sockets, etc
• Knows one or more of Wireframes/ Prototyping/ Functional Documentation of business.

4-10 LPA based on experience and on performance in the interview round (70% Fixed - 30% Variable Incentive based on performance/delivery schedule)

(We do ZERO deductions since the salary will be paid from US/Singapore)