Ruby on Rails Developer | Chennai

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

Skill set Key words

Java17, Java Spring Boot, Kubernetes/AKS/Docker(Knowledge), Microservices, (MongoDB/DynamoDB)

Role and Resposbilities :

•  Hands on experience in Java back-end development and skills with Spring-boot framework

•  Real life experience with Continuous Delivery principles and related tools (Kubernetes, AKS, Docker)

•  Expertise with Microservices design

•  Understanding of the Design Patterns, Architectural Blueprints, UML and Application Design

•  Experience in stateful application and web sessions

•  Experience with MongoDB, DynamoDB

•  Excellent communication skills and an ability to work in a team

• Hands-on experience in modern web-development using .Net core, C#, Angular2+, Javascript, HTML5, CSS
• Expertise in developing services (SOAP-WCF and REST)
• Expertise in web development frameworks like ASP.NET MVC
• Good knowledge of database concepts and Microsoft SQL Server
• Solid foundation in computer science, with strong competencies in data structures, design patterns, concurrency, algorithms, and software design
• Experience working in any of the JavaScript frameworks like Ember.js, AngularJS, or ReactJS is a bonus.
• Strong analytical and troubleshooting skills.
• Ability to work as an individual contributor.
• Flair to learn new technologies and thrive in an agile environment.

About Us

Aura is developing a platform to help companies/communities mint, buy, trade and sell NFTs in the easiest manner possible. Developing a state of the art store front customized to the community and a user friendly interface to unlock the digital growth of companies in the gaming, art, music, etc space by leveraging the power of NFTs. We are assembling a high performing team from the tech ecosystem to build this product and compete with the likes of NBA TopShot.

Requirements

• Integration of user-facing elements developed by a front-end developers with server side logic
• Building reusable code and libraries for future use
• Optimization of the application for maximum speed and scalability
• Implementation of security and data protection
• Design and implementation of data storage solutions

Skills and Qualifications

• 2+ years of experience in Node.js. Basic understanding of front-end technologies and platforms, such as JavaScript, HTML5, and CSS3
• Good understanding of server-side CSS preprocessors, such as LESS and SASS
• Integration of multiple data sources and databases into one system
• Management of hosting environment, including database administration and scaling an application to support load changes
• Understanding differences between multiple delivery platforms such as mobile vs desktop, and optimizing output to match the specific platform
• Implementing automated testing platforms and unit tests
• Proficient understanding of code versioning tools, such as Git
• Proficient understanding of security principles
• Understanding of “session management” in a distributed server environment
• Must have an understanding of SQL and NoSQL databases like Postgres, MySQL, Mongodb etc.
• Must have an understanding of Cloud: AWS or GCP
• Must have a good understanding of data structures and Algorithms

Benefits

• Work on the cutting edge of blockchain technology and the upcoming use-case of NFTs (Non Fungible Token)
• Be a part of an early stage startup with funding from founders of Polygon

Strong proficiency with one of the Vue.js, Angular JS, React JS JavaScript Techologies
2. Knowledge of Node.js and frameworks available for it , such as Express JS, Strong Loop, etc
3. Understanding the nature of asynchronous programming and Promises and its quirks and workarounds
4. Good understanding of server-side templating languages (such as Jade, EJS, etc depending on your technology stack)
5. Good understanding of server-side CSS pre-processors such as Styles, Less
6. Basic understanding of front-end technologies, such as HTML5, CSS3, and Bootstrap
7. Understanding accessibility and security compliance
8. User authentication and authorization between multiple systems(Internal or Third party), servers, and environments
9. Integration of multiple data sources and databases into one system
10. Understanding fundamental design principles behind a scalable application
11. Understanding differences between multiple delivery platforms, such as mobile vs. desktop, and optimizing output to match the specific platform
12. Implementing automated testing platforms and unit tests
13. Proficient in code versioning tools, such as Git or TFS

• Expert knowledge of computer science, with strong competencies in data structures, algorithms,

  and software design.

• Strong understanding of end-to-end architectures and development frameworks; knowledge

  across tiers in a multi-tier cloud environment including load balancers, web servers, application

  containers, data stores, and distributed caches.

• Minimum 6 years of experience with deep technical knowledge and hands on skills in Java.

• Has worked extensively on caching technologies such as Redis, memcache.

• Should be strong with Data Strcutures, Algorithms & OOPs concepts.

• Worked on NoSQL databases such as MongoDb.

• Designed and developed highly scalable multi-threaded large scale distributed systems.

• Well versed with services and micro-services architecture.

• • Usage of containers, virtual machine systems, cloud computing.