MERN Stack Developer

About NEXUS SP Solutions

European tech company (Spain) in telecom/IT/cybersecurity. We’re hiring a Part-time Automation Developer (20h/week) to build and maintain scripts, integrations and CI/CD around our Odoo v18 + eCommerce stack.

What you’ll do

• Build Python automations: REST API integrations (vendors/payments), data ETL, webhooks, cron jobs.

• Maintain CI/CD (GitHub Actions) for modules and scripts; basic Docker.

• Implement backups/alerts and simple monitors (logs, retries).

• Collaborate with Full-Stack dev and UX on delivery and performance.

Requirements

• 2–5 yrs coding in Python for integrations/ETL.

• REST/JSON, OAuth2, webhooks; solid Git.

• Basic Docker + GitHub Actions (or GitLab CI).

• SQL/PostgreSQL basics; English for daily comms (Spanish/French is a plus).

• ≥ 3h overlap with CET; able to start within 15–30 days.

Nice to have

• Odoo RPC/XML-RPC, Selenium/Playwright, Linux server basics, retry/idempotency patterns.

Compensation & terms

• ₹2.5–5 LPA for 20h/week (contract/retainer).

• Long-term collaboration; IP transfer, work in our repos; PR-based workflow; CI/CD.

Process

1. 30–45’ technical call. 2) Paid mini-task (8–10h): Python micro-service calling a REST API with retries, logging and unit test. 3) Offer.

We are looking for a highly skilled MERN Stack Developer who is passionate about building seamless user interfaces and robust backend systems. The ideal candidate will have strong expertise in ReactJS for UI development and hands-on experience in Node.js API development. You will play a crucial role in developing and maintaining scalable web applications using the MERN (MongoDB, Express.js, React.js, Node.js) stack.

Responsibilities:

• Frontend Development:
• Build responsive and dynamic user interfaces using ReactJS.
• Develop reusable components, UI libraries, and ensure excellent user experience.
• Optimize applications for maximum speed and scalability.
• Work with tools like Redux, React Hooks, and other state management libraries.
• Backend Development:
• Design and develop RESTful APIs using Node.js and Express.js.
• Build secure, scalable, and efficient server-side applications.
• Integrate third-party APIs and services when required.
• Database Management:
• Work with MongoDB to design and manage collections, queries, and indexes.
• Ensure smooth integration of database operations with the backend.
• Collaboration:
• Work closely with designers, project managers, and other developers to define project requirements and deliverables.
• Conduct code reviews and ensure clean, maintainable, and testable code.
• Testing and Deployment:
• Write unit tests and integration tests for both frontend and backend components.
• Deploy applications to cloud environments (AWS, GCP, or similar platforms).
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Skills and Qualifications:

• Strong proficiency in ReactJS:
• Experience in creating dynamic and responsive UI components.
• Knowledge of modern React features such as Hooks, Context API, and functional components.
• Hands-on Node.js API Development:
• Strong experience in Express.js to build RESTful APIs.
• Understanding of asynchronous programming and event-driven architecture.
• Good knowledge of MongoDB:
• Hands-on experience with designing collections, writing queries, and data modeling.
• Proficient in JavaScript and ES6+:
• Strong understanding of modern JavaScript, including DOM manipulation.
• Familiarity with:
• State Management Libraries (e.g., Redux, MobX).
• Version Control (Git and GitHub).
• Frontend Tools like Webpack, Babel, and NPM/Yarn.
• API Integrations and tools like Postman or Swagger for testing APIs.
• Strong understanding of UI/UX design principles:
• Ability to work with design tools (e.g., Figma, Sketch, or Adobe XD) to bring designs to life.
• Problem-solving mindset and ability to write clean, efficient, and maintainable code.

Nice-to-Have Skills:

• Experience with TypeScript.
• Knowledge of GraphQL.
• Experience with containerization tools like Docker.
• Familiarity with deployment tools (CI/CD pipelines).

Experience:

• 0-2 years of experience as a MERN Stack Developer or relevant roles.

Benefits:

• Competitive salary based on experience.
• Opportunity to work on exciting and impactful projects.
• Collaborative and dynamic work environment.
• Career growth and learning opportunities.

Get to Know our Team:

In our Full stack Engineering department, we build the scalable, fault-tolerant systems and APIs that host our core business logic. Our systems cover all major areas of our business: such as TAM SAM, calculator, lead generation, campaign execution & data modeling. Most importantly though, we hire great people and empower them to be successful. Whether it’s building new projects or reimagining our existing business, you’ll make a big impact as part of the Full stack Engineering team.

The Opportunity: 

Swabhav is looking for developers to work on mission critical systems that deal with the designing and development of APIs.

In this Role, you’ll get to

• Lead development of features, experiments, technical projects and complex systems.
• Be a technical architect, mentor, and driver towards the right technology.
• Continue to evolve our architecture and build better software.
• Be a major contributor to our agile and scrum practices. 
• Get involved with software engineering and collaborate with server, other client, and infrastructure technical team members to build the best solution.
• Constantly look for ways to improve our products, codebase and development practices. 
• Write great code and help others write great code.
• Drive Technical decisions in the organization.

What You’ll Need to Succeed

• 3-6 years’ experience under your belt developing performance-critical applications that run in a production environment using Node Js, React Js or Next Js, PostgreSQL.
• Experience in full ownership of the systems involved.
• Hands on experience working with CRM platforms, Third party app integrations or Heavy file processing & Restful APIs.
• You understand that different applications have different data requirements.
• Good understanding of algorithms and data structures
• Strong coding ability.
• You are passionate about the craft of software development and constantly work to improve your knowledge and skills.
• Excellent communication skills.

It’s Great If You Have

• Experience with Scrum/Agile development methodologies.
• Experience building products.
• Core engineering infrastructure tools like Git for source control.

Technical & Professional Requirements

• MERN stack developer should have the ability to translate Wireframes and PSD Designs into functional web apps.
• Binding of UI elements to JavaScript object models
• Creating RESTful services with Node.js
• MERN stack developer must have proven experience in front & back-end development
• Work in a cross-functional team to deliver a complete user experience
• Reactjs Nodejs developer must know MongoDB, Express, Node.js, & React.
• Write code that is cross-platform and cross-device compatible
• MERN full stack developer must have the ability to wear many hats and learn new technologies quickly
• Understanding & proficiency in REST APIs.
• Integration of data storage solutions [RDBMS, NoSQL DB]

Responsibilities & Skills

• MERN Fullstack eCommerce developer is responsible for writing reusable, testable, and efficient code
• Design and implementation of low-latency, high-availability, and performant applications
• Implementation of security and data protection
• MERN software developer must have good communication & interpersonal skills

SellerGeni is an early-stage VC Funded SAAS Product in the Ecommerce Growth space. Our products GrowZ and SmartPlug enable sellers on Amazon to grow their sales and improve the quality of their listings through automated tools. Our vision is to simplify Growth across all ecommerce channels. We make traffic generation as simple as launching a Shopify website. You will be working closely with key stakeholders across the organization and leading a team of motivated engineers and professionals trying to change the status quo in online business growth. Join us if you love solving real-world problems with technically robust solutions.

Open to SDE-2, SDE-3, FSE & SWE.

What you will be doing

• Write test-driven code for Client and Server side application
• Creating functional codes that implement product requirements
• Participating in the design and creation of scalable software
• Testing and fixing bugs and/or other coding issues
• Take ownership of code, tasks and system architecture
• Brainstorming to scale the system for millions of users
• Mentoring juniors and champion the Agile Development Practices

What you need to have

• Knowledge of Javascript back-end languages & frameworks (e.g NodeJS, ExpressJS, GraphQL, TypeScript etc)
• Knowledge of Javascript front-end frameworks (e.g.NextJS, ReactJS, Angular etc)
• Experience in SQL/NoSQL databases (e.g. MongoDB, MySQL, DynamoDB, etc)
• Experience in building and maintaining large-scale production (e.g Redis, Jobs, Queue, Async sockets, etc)
• Knowledge of modern javascript libraries (e.g JWT, Webpack, Browserify, jQuery, Bootstrap, Semantic etc)
• Decent understanding of networking technologies (e.g TCP, HTTP, websockets, server-sent events, etc)
• Excellent communication and teamwork skills
• Good understanding of System design, architecture and Web Security
• Knowledge of version control software like Git, Github, BitBucket

Nice to have

• GSoC (or) Open Source contributions
• Prior startup (or) SAAS product experience
• Experience with building B2B products
• Amazon SP-API, MWS and advertising API
• Consumer Web Development Experience for High-Traffic, queue based applications
• Software security and SDLC
• UI/UX Product design & decision
• Experience in development workflow integrations (e.g CI/CD, Docker, Kube, pods, etc)
• Experience in building REST APIs, server-side architecture
• Decent understanding of Cloud & DevSecOps (e.g ECS ELB, SSM, SQS, Lambda, Kafka etc)

Benefits

• Competitive Salary & Equity
• MacBook Pro
• Flexible Work Timings
• Work With Experienced Team (Ex Amazon, Paytm, Oracle & GSoCers)

Total Experience : 2-6 years Relevant Experience: 2-3+ years