MERN Stack developer

Senior Backend Engineer

Node.js, System Design & Production Platforms

📍 Mumbai (On-site) | Full-time | 5+ years

About the Role:

Unico Connect is an AI-first technology partner that builds custom mobile, web, and AI products for clients across multiple geographies.

We are hiring a Senior Backend Engineer to own the backend architecture of a complex production AI platform on a dedicated client engagement: API design and data modelling, multi-tenancy, orchestration of long-running agent workloads, and the services that manage user projects and generated output.

We are open to full stack engineers whose primary strength and interest is backend. If you have shipped full stack work but the backend is where you do your deepest engineering, you are a fit for this role.

The mandatory requirement for this role is hands-on production experience as a senior backend engineer building complex, scalable systems in Node.js, with end-to-end ownership of architecture, data, and operations on at least one live platform.

The role is hands-on and architectural.

Expect to design system architecture, lead a small group of backend engineers, build the hardest parts yourself, set engineering standards, and partner closely with frontend, AI, and DevOps engineers.

A typical week includes an architecture decision on a new service, hands-on implementation of a critical path, a code review with mid-level engineers, and a working session with the AI engineer on an integration contract.

Responsibilities:

System Architecture

Own the backend architecture across engagements.

Make and document decisions on service boundaries, data models, API contracts, deployment topology, and trade-offs.

Hands-on Backend Delivery

Lead by example on complex modules, performance-critical paths, and high-risk areas using Node.js (Express, NestJS, Fastify) with TypeScript.

Pick up Python (FastAPI) where engagements require it.

Database Design and Performance

Drive PostgreSQL schema design, indexing, query optimisation, migrations, and capacity planning.

Set the data-modelling standard across the pod.

Caching, Queues, and Workflows

Design caching (Redis), event-driven patterns (Kafka, RabbitMQ, SQS, NATS), and long-running workflow orchestration (Temporal, BullMQ, Celery, or equivalent).

Handle retries, idempotency, and failure recovery.

Multi-Tenancy and Platform Patterns

Design and implement multi-tenant data isolation, RBAC, audit logging, and resource quotas appropriate to enterprise-grade products.

API and Integration Design

Set the standard for REST, GraphQL, and gRPC contracts.

Drive versioning, authentication (OAuth, JWT, SSO), security by default, and developer ergonomics.

Observability and Operations

Instrument services with OpenTelemetry, Prometheus, and Grafana.

Define SLOs, lead incident response, and write postmortems.

Code Quality and Mentorship

Run code reviews, define conventions, mentor mid-level engineers, and raise the engineering bar.

AI-Assisted Engineering Discipline

Use Claude, Cursor, and similar tools day to day.

Set the team standard for prompts, patterns, AI-assisted review, and validation of AI-generated backend code.

Client Engagement

Represent Unico Connect in technical conversations with customers.

Defend architectural decisions, communicate trade-offs, and manage scope.

Requirements:

Hands-on Production Experience as a Senior or Lead Backend Engineer in Node.js (Mandatory)

Must have personally built and shipped complex production systems in Node.js, owning architecture, data, and operations on at least one live engagement.

Full stack engineers whose deepest work is on the backend qualify.

POCs and internal tools alone do not qualify.

5+ Years of Professional Backend Engineering Experience

With at least 1 to 2 years in a senior or lead role with direct responsibility for technical decisions and team output.

Deep Node.js and TypeScript Proficiency

Strong with Express, NestJS, or Fastify.

Comfort with async patterns, streams, worker threads, and performance profiling.

Python as a Strong Plus

Hands-on production experience with FastAPI, Django, or Flask is a meaningful advantage.

Willingness and demonstrated ability to pick up Python as engagements demand is required.

PostgreSQL Depth

Schema design, normalisation, indexing, query performance, migrations, and at least one production system where you owned the data model end to end.

Caching and Event-Driven Architecture

Hands-on with Redis (or equivalent) and message queues or event-driven patterns (RabbitMQ, SQS, Kafka, NATS).

AWS Depth

Hands-on production experience with EC2, S3, RDS, IAM, VPC, ECR, and at least one of EKS, ECS, or Lambda.

Comfort owning deployment, monitoring, and cost.

System Design and End-to-End Ownership

Able to take an ambiguous problem, break it into components, evaluate alternatives, produce an architecture that holds up under review and load, plan execution, and ship with limited supervision.

AI-Assisted Engineering Experience

Daily use of Claude, Cursor, Copilot, or equivalent.

Strong discipline for reviewing and validating AI-generated backend code.

Excellent Written and Spoken English

Experience working directly with international clients.

Confident defending architectural choices in writing and in review.

Nice to Have:

• Workflow orchestration (Temporal, Airflow)
• GraphQL (Apollo, gRPC)
• Sandboxed execution environments
• Multi-tenant SaaS experience
• OpenTelemetry instrumentation
• Prior agency or consulting experience

We are seeking a skilled MERN Stack Developer to join our dynamic development team. The ideal candidate will be proficient in MongoDB, Express.js, React.js, and Node.js, and will play a key role in building and maintaining web applications.

Key Responsibilities:

• Frontend Development: Develop user-facing features using React.js, ensuring appealing and responsive user interfaces.

• Backend Development: Build efficient and scalable server-side systems using Node.js and Express.js.

• Integration: Integrate front-end components with server-side logic, ensuring seamless communication between the two.

• Data Management: Implement data storage solutions using MongoDB and other relevant technologies.

• Troubleshooting: Identify and address bugs, glitches, and performance issues to maintain application functionality.

• Collaboration: Work closely with cross-functional teams to conceptualize, define, and implement new features.

• Innovation: Keep abreast of emerging technologies and trends to contribute to continuous improvement.

Required Skills and Qualifications:

• React Proficiency: In-depth knowledge of React.js and its core concepts for building dynamic user interfaces.

• Node.js and Express: Strong expertise in Node.js and Express.js to create efficient and scalable backend systems.

• MongoDB: Experience with MongoDB for data storage and management.

• Full-Stack Development: Ability to work on both frontend and backend development.

• Problem-Solving: Strong analytical and problem-solving skills.

• Communication: Excellent communication and teamwork skills.

Preferred Qualifications:

• Experience with RESTful APIs and GraphQL.

• Familiarity with version control systems like Git.

• Understanding of Agile methodologies.

Beyond strong technical ability and cultural fit, we are looking for someone who demonstrates:

• Minimum 1 year of professional web development experience
• A portfolio showcasing real-world projects or contributions (personal or professional)
• Strong foundation in HTML, CSS, and JavaScript, with working experience in modern frameworks
• Practical experience with React (mandatory)
• Ability to build responsive, user-friendly interfaces with attention to UX best practices
• Experience integrating APIs and working with JSON-based data
• Familiarity with version control systems such as Git
• Basic understanding of backend concepts, preferably with exposure to Node.js, Java, or Python
• Ability to debug, troubleshoot, and improve existing codebases
• Good understanding of performance optimization and cross-browser compatibility
• Strong time management skills with the ability to handle multiple tasks effectively
• Excellent communication and teamwork skills, with a proactive and learning-oriented mindset

Job Summary:

We are seeking an experienced Back-end Developer to join our IT team. You will be responsible for the server-side of web applications. If you have excellent programming skills and a passion for developing or improving applications, we would like to meet you.

As a Back-end Developer, you will work closely with our team to ensure system consistency and enhance the user experience. Ultimately, you should be able to develop and maintain functional and stable web applications that meet our company's needs.

Responsibilities and Duties:

• Participate in the entire application lifecycle, focusing on coding and debugging
• Write clean code to develop functional web applications
• Troubleshoot and debug applications
• Perform unit tests to optimize performance
• Manage cutting-edge technologies to improve legacy applications
• Collaborate with front-end developers to integrate user-facing elements with server-side logic
• Gather and address technical and design requirements
• Provide training and support to internal teams
• Build reusable code and libraries for future use
• Liaise with developers, designers, and system administrators to identify new features required

Skills and Qualifications:

• Proven work experience as a Back-end Developer
• In-depth understanding of the entire web development process (design, development, and deployment)
• Hands-on experience with JS, ES6, Node.js, Express.js, MongoDB, building REST APIs, and GraphQL
• Excellent analytical and time management skills
• Strong teamwork skills with a problem-solving attitude
• BSc/BE or BTech degree in Computer Science or a relevant field

Skills:

• Node.js
• MongoDB
• JavaScript
• Express

We are looking for a Full Stack Web Developer with 4-6 years’ experience as a web developer in the latest of technologies. As a Full Stack Developer, you will be responsible for designing and implementing web applications that deliver a seamless user experience. You will work on both the front-end and back-end development, ensuring the entire application functions effectively.

Skills Required:

• Good communication and client interfacing skills.
• Solid fundamentals in core JavaScript concepts while working on web projects for 4-6 years.
• Proficient with Frameworks like Node.js/Nest.js, Angular/React/Vue.js/Next.js along with related technologies & frameworks like HTML, CSS, Bootstrap, Material UI.
•  Good experience with Relational and/or NoSQL databases.
•  Hands-on experience in building high-quality Web applications.
• Good knowledge of at least one major cloud service provider (AWS, Azure, Google Cloud).
• Good knowledge of Docker, Docker Compose.
•  Basic Understanding of Kubernetes.
•  Good experience with Git and branching strategy (preferably GitFlow)
•  Good architectural & design skills.
•  Strong analytical, problem solving, debugging and troubleshooting skills.
•  Strong understanding of emerging technologies, standards, and best practices for development.
•  Software development experience with significant time spent working on Cloud technologies preferred.
• Agile/Scrum methodology experience.

Role & Responsibilities:

• Go to the person of the Project lead for complex feature implementations.
• Understand requirements on its own and implement them.
• Create efficient, reusable, and scalable code for both front-end and back-end.
• Optimize applications for maximum performance and responsiveness.
•  Troubleshoot and debug issues in a timely manner.
• Write and maintain technical documentation.
•  Stay up to date with the latest industry trends and best practices in web development.
•  Participate in code reviews to maintain code quality and enhance team collaboration.
• Guide junior members in the team to help them improve their skills.

• Expertise with NodeJS (extensively using ExpressJS), AngularJS and MySQL
• Rich user interface development experience with HTML5, JQuery, w3css/bootstrap etc and JavaScript frameworks like AngularJS and Angular 
• Expertise in building real-time web applications using MQTT, Websocket, Socket.IO, and EventSource frameworks
• Comfortable with developing MVC architecture-based code
• Comfortable in using at least one of the Graph/Chart libraries
• Ability with report generation from HTML contents
• Skilled in implementing security features across the applications and components
• Experience with tools usage - Code quality, Memory/CPU profiling tools
• Skilled with code optimization techniques
• Experience with docker container usage
• Experience with LDAP is a plus
• Strong troubleshooting techniques
• The strong defect resolution process for minimized latency
• Familiarity with confluence management (JIRA)
• Good to have a basic understanding of PHP frameworks like Yii, Codeigniter and databases like  MongoDB
• Good to have strong networking fundamentals, prior working experience in network technologies and protocols
• Ability to build supportability features to reduce the defects in software components
• Knowledge of GNU tools, revision control software (SVN, Git, etc.) and development lifecycle is a plus

Exp. Level: 5+ Yrs

Proven experience as a. NET Developer

Familiarity with the ASP. NET core framework, SQL Server, Web API, and Microservices

Understanding of Agile methodologies

Excellent troubleshooting and communication skills

Required Skills: ASP. Net Core Web API, and React Js

 Kindly Share the Profile through LinkedIn

ID: linkedin.com/in/ranjini-c-n-36b674131

We are looking for a Developer who is proficient with Node and has at least 1-3 years of relevant experience. Your primary role will be on developing microservices, while ensuring good coding practices and architecture. You will have end to end ownership of the services you develop, to ensure it is robust and easy to maintain. You will coordinate with the rest of the team working on different layers of the infrastructure. Therefore, a commitment to collaborative problem solving, and quality product is important.

Roles and Responsibilities

• Integrating and maintaining Node micro services
• Proficient in RESTful APIs and API communications, especially to consume data from and/or push data into MongoDB for Web and mobile applications
• Proficient on modeling applications on NOSQL databases(preferably MongoDB)

Desired Candidate Profile

• Strong coding experience in Node JS.
• Should have experience with microservice architecture
• Compile and analyze data, processes, and codes to troubleshoot problems and identify areas for improvement

Nice to have:

• Some experience with queues like like Redis,SQS,etc
• Experience with cloud solutions like Lambda, Docker etc
• Experience in DevOps and related practices to improve development lifecycle, continuous delivery with high quality is an advantage.
• Deploy server/related components to staging, live environments.
• Some exposure to React Frontend implementation, deeper JS skills

We need an experienced engineer who can lead our existing team and product. 

Job description 

• Must possess strong analytical skills to be able to break down complex problems into smaller atomic units of work.
• Must be able to develop application modules independently and fix any bugs promptly.
• Do unit testing for the development work carried out.
• Act as a mentor to the junior developers and provide technical guidance.
• Troubleshoot problems and provide solutions.
• Conduct and participate in project planning & scheduling, design discussions, and provide assistance during testing.
• Willing to learn and adopt new technologies in a short period of time as required by the project.
• Will require to produce technical documentation as the requirements of the project.
• Remain up to date with the modern industry practices involved in designing & developing high-quality software.
• Should be able to do performance engineering and identify and fix bottlenecks

Job Requirements

• Good knowledge of Node.js, Express.js, React
• Need clear understanding of JavaScript and Typescript.
• Sound understanding of MVC and design patterns.
• Excellent grasp of data structures and designing and developing ReST APIs.
• Good skills of NoSQL (MongoDB or equivalent).
• Must have at least 3 years’ experience in MEAN/MERN Stack development.
• Experience in developing responsive web applications.
• Good communication skills.
• Sound understanding of Agile and Scrum methodologies and ability to participate in local and remote Sprints.
• Good grasp of UI / UX concepts.
• Should have experience in using Git & VSCode.
• Knowledge of AWS and Postman will be considered positively.