Lead Backend Developer

Why This Role Matters

Our backend is what keeps checkout, RTO, and payments fast and reliable at ~$2B GMV across 15,000+ merchants. As an SDE 2 you own services end to end, make the architecture calls that keep them performant, and set the technical bar for the engineers around you. The trade-offs you pick show up directly in merchant conversions and platform reliability - this is a builder's seat with real ownership.

What You'll Own

• Design and build backend services primarily in Node.js/NestJS, with Go for select services, backed by Postgres, Mongo, and Redis.
• Own event-driven flows on Kafka - throughput, ordering, and failure handling.
• Make and document the architecture and trade-off decisions for systems you lead.
• Ship features end to end, dropping into the frontend (React/Svelte) when it's the fastest path.
• Strengthen CI/CD, observability, and deployments on AWS.
• Review code, mentor SDE 1s and AEs, and raise the quality bar on the team.
• Take ambiguous problems and drive them to delivery with minimal hand-holding.

Who You Are

• Strong backend engineer in JavaScript/TypeScript on Node.js/NestJS (our primary stack); working knowledge of Go, or ready to pick it up.
• Solid at data modelling across Postgres and Mongo, and knows when Redis earns its place.
• Has built and scaled event-driven systems (Kafka or equivalent).
• At home on the backend but happy to work across the stack in React/Svelte.
• Thinks in systems - scalability, reliability, maintainability - not just features.
• Has mentored engineers and owns code quality and delivery, not just their own tickets.
• Communicates clearly and does well with ambiguity in a fast-moving team.

About NonStop io Technologies

NonStop io Technologies is a value-driven company with a strong focus on process-oriented software engineering. We specialize in Product Development and have a decade's worth of experience in building web and mobile applications across various domains. NonStop io Technologies follows core principles that guide its operations and believes in staying invested in a product's vision for the long term. We are a small but proud group of individuals who believe in the 'givers gain' philosophy and strive to provide value in order to seek value. We are committed to and specialize in building cutting-edge technology products and serving as trusted technology partners for startups and enterprises. We pride ourselves on fostering innovation, learning, and community engagement. Join us to work on impactful projects in a collaborative and vibrant environment.

Brief Description

We're seeking an experienced Senior Backend Engineer/Tech Lead to join our team. As a backend engineer, you will be responsible for designing, developing, and deploying scalable backends for the products we build at NonStop. This includes APIs, databases, and server-side logic. Also, guiding the mentoring the junior team members

Responsibilities

• Design, develop, and deploy backend systems, including APIs, databases, and server-side logic
• Write clean, efficient, and well-documented code that adheres to industry standards and best practices
• Code Quality: Ensure code quality through code reviews, adherence to best practices, and continuous improvement
• Mentorship: Guide and mentor team members, fostering growth and innovation
• Collaboration: Work closely with stakeholders to align technical goals with business objectives
• Problem-Solving: Analyze and resolve technical challenges promptly
• Innovation: Stay updated with the latest technology trends and integrate them into solutions

Requirements

• At least 5+ years of experience building scalable and reliable backend systems
• Strong expertise in NodeJS/NestJS, Express, PostgreSQL
• Experience with microservices architecture and distributed systems
• Proficiency in database design (SQL and NoSQL)
• Knowledge of cloud platforms (AWS, Azure, or GCP) and CI/CD pipelines
• Deep understanding of design patterns, data structures, and algorithms
• Hands-on experience with containerization technologies like Docker and orchestration tools like Kubernetes
• Familiarity with Frontend Development Technologies (React, JavaScript, HTML, CSS)
• Exceptional communication and leadership skills
• Strong understanding of object-oriented programming principles and design patterns
• Familiarity with automated testing frameworks and methodologies
• Excellent problem-solving skills and attention to detail
• Strong communication skills and ability to effectively lead and maintain a collaborative team environment

Why Join Us?

• Opportunity to work on a cutting-edge healthcare product
• A collaborative and learning-driven environment
• Exposure to AI and software engineering innovations
• Excellent work ethic and culture

If you're passionate about technology and want to work on impactful projects, we'd love to hear from you!

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

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 Backend Engineer for a dedicated client engagement building an AI-powered application builder platform.

The backend is the operational core of the product: it manages user projects and sessions, coordinates long-running AI agent workloads, maintains project state, and serves as the integration layer between the frontend, the AI system, and the underlying infrastructure.

The mandatory requirement is hands-on production experience shipping Node.js services, with end-to-end ownership of API design, data modelling, and at least one production system involving background job processing or event-driven patterns.

Responsibilities

API and service development: Design and build REST APIs in Node.js with TypeScript. Cover authentication, session management, input validation, structured error handling, streaming responses (SSE, WebSockets), and rate limiting. Maintain clean API contracts that the frontend and AI system can rely on.

Database design and management: Own PostgreSQL schema design for product domains including user accounts, projects, file trees, session state, and generated artefacts. Write efficient queries, manage migrations, and optimise for read patterns that serve a real-time editor experience.

Caching strategy: Implement and maintain caching with Redis for session data, project state, and frequently read configuration. Design cache invalidation logic that keeps the editor experience consistent without stale reads.

Queue and background job management: Implement and operate background job infrastructure using BullMQ or equivalent. AI agent runs are long-running and stateful; handle retries, failure states, priority queues, and concurrency limits.

AI system integration: Build the integration layer between the backend and the AI agent system. Manage job dispatch, result handling, streaming output to the frontend, and error propagation.

Multi-tenancy and access control: Implement tenant data isolation, RBAC, and resource ownership enforcement across all API surfaces.

Observability and reliability: Instrument services with structured logging, metrics, and tracing. Write defensive code with sensible timeouts, fallback behaviour, and circuit breaking on external dependencies.

Testing and code quality: Write unit and integration tests for the services you ship. Review the work of peers and contribute to shared engineering conventions.

Requirements

• Hands-on production Node.js experience (mandatory) — must have personally shipped at least one feature area end to end in a production Node.js service, owning API design, data modelling, and testing.

• 3 to 5 years of professional backend engineering experience. Candidates with slightly less time but strong demonstrated ownership are welcome to apply.

• Strong Node.js and TypeScript. Production experience with Express, NestJS, or Fastify. Solid with async patterns, streaming, error handling, and building services that run reliably under sustained load.

• PostgreSQL depth. Schema design, query writing, indexing, and migrations on at least one production system.

• Redis and caching. Production experience using Redis for caching and session management. Understands cache invalidation trade-offs.

• Queue and background job systems. Hands-on with BullMQ, RabbitMQ, SQS, or equivalent. Experience managing retries, dead-letter queues, job priority, and concurrency control.

• AWS working knowledge. Comfortable with EC2, S3, RDS, SQS, and IAM. Familiar with Docker and basic deployment and environment management.

• Strong written and spoken English. Able to communicate clearly with engineers across disciplines and write precise technical documentation.

Nice to Have

Experience integrating with AI or LLM services (streaming responses, structured outputs, retry patterns); WebSocket or SSE implementation for real-time features; multi-tenant SaaS product experience; GraphQL; OpenTelemetry instrumentation; prior work on developer tools or editor-style products.

Job Title : Senior Backend Engineer – Node.js & TypeScript

Experience : 4+ Years

Employment Type : Contract – 3 Months

Location : Pune

Work Mode : On-site

Working Hours : 03:00 PM to 11:00 PM OR 03:00 PM to 12:00 AM

Time Zone : Minimum 4-hour overlap with Eastern Time (ET)

About the Role :

We are looking for a Senior Backend Engineer to design, develop, and scale an AI-led digital platform. The role involves working closely with the Founder/CEO and technical team on architecture, product development, innovation, and end-to-end feature ownership.

Mandatory Skills :

Node.js, TypeScript, REST, GraphQL, PostgreSQL, SQL, Prisma / TypeORM / Sequelize, AWS (ECS, EC2, S3, RDS, Lambda), Airbyte / dbt / Airflow / AWS Glue, Data Warehousing, Event-Driven Architecture, Message Queues, CI/CD, Automated Testing, Backend Architecture, Scalability & Performance.

Key Responsibilities :

• Design and develop scalable backend services using Node.js and TypeScript.
• Build and optimize REST and GraphQL APIs.
• Work with PostgreSQL, SQL, and ORMs such as Prisma / TypeORM / Sequelize.
• Design data pipelines using Airbyte, dbt, Airflow, or AWS Glue.
• Manage and optimize AWS infrastructure including ECS, EC2, S3, RDS, and Lambda.
• Implement CI/CD, automated testing, event-driven architectures, and message queues.
• Optimize API performance, scalability, reliability, and data warehouse solutions.
• Own features end-to-end from design to production.
• Participate in code reviews, on-call support, and production troubleshooting.
• Collaborate with Product, QA, and Engineering teams and mentor junior developers.
• Work closely with the Founder / CEO on technical solutioning and product innovation.

Requirements :

• 4+ years of hands-on Node.js & TypeScript backend development.
• Strong experience with AWS, PostgreSQL, SQL, APIs, and backend architecture.
• Hands-on experience with data pipelines and data warehousing.
• Experience with CI/CD, automated testing, event-driven systems, and message queues.
• Strong problem-solving skills and end-to-end ownership mindset.
• Ability to work independently in a fast-paced environment.
• Good communication and collaboration skills.
• Bachelor's degree in Computer Science, IT, or a related field.

Preferred :

• Terraform / CloudFormation and Infrastructure as Code.
• Docker / Kubernetes and strong DevOps exposure.
• AWS backup / disaster recovery experience.
• Exposure to GCP / Azure.
• Startup / early-stage product development experience.

You’ll work on a data-intensive application that uses APIs to collect public data, processes and transforms that data, extracts user signals, and builds user profiles from those signals.

We need someone who has personally built and owned production systems end to end — from architecture and database design to API integrations, background job processing, data pipelines, frontend development, deployment, and production debugging.

You should be comfortable handling asynchronous workloads, designing reliable background jobs, processing large volumes of data, managing failures and retries, and optimizing database queries and application performance.

This is a hands-on engineering role. We’re looking for someone who writes code, solves real technical problems, and takes ownership of features from idea to production. Experience building data-intensive applications and backend processing systems is important.

Strong Software Engineer fullstack profile using NodeJS, Python, and React

2

Mandatory (Experience) - Must have 6+ YOE in Software Development using Python and NodeJS (For backend) & React (For frontend)

3

Mandatory (Core Skills 1): Must have strong experience in working on Typescript

4

Mandatory (Core Skills 2): Must have experience in message based systems like Kafka, RabbitMq, Redis

5

Mandatory (Core Skills 3): Databases - PostgreSQL & NoSQL databases like MongoDB

6

Mandatory (Company) - Product Companies Only

7

Mandatory (Education) - B.Tech or Dual degree (Btech and Mtech or Integrated Msc/MS) from Tier 1 Engineering Institutes (IITs, not NITs). Candidates from other institutions will not be considered unless they come from top-tier product companies

8

Mandatory (Note) : This role is a hybrid role (2 days WFO)

9

Preferred (Experience): Experience in Fin-Tech, Payment, POS and Retail products is highly preferred

10

Preferred (Mentoring): Experience in mentoring, coaching the team.

Backend Developers

• Contract To Hire (Initial Engagement: 6 months)

Experience: 5+ years

Mandatory Skills:

● Node.js

● Python

● MongoDB

● PostgreSQL

● REST API design and development

● Backend architecture and service design

● Database design, indexing and query optimisation

● Performance tuning

● Authentication/authorisation

● Third-party integrations

● Asynchronous processing and background jobs

● Logging, monitoring and debugging

● Git and collaborative development

● Scalable, maintainable and testable backend services

● Architecture discussions, code reviews, debugging and production support

Good to have:

● Microservices

● Docker

● Cloud platforms

● Redis

● Message queues

● CI/CD

● Observability

We are hiring a Node.js Developer to build fast, scalable backend services and APIs.

Responsibilities

• Build REST and GraphQL APIs with Node.js, Express and NestJS
• Design data models in MongoDB and PostgreSQL
• Write clean, tested TypeScript
• Improve service performance, caching and reliability

Requirements

• 1+ years of backend development with Node.js
• Experience with Express or NestJS
• Solid understanding of databases and async programming

We are building HypeMuse, an event-based photo and GIF discovery platform for sports games, concerts, and live events.

Our current backend is built with Laravel/PHP, and we are planning to rebuild the backend using Node.js. We are looking for a strong backend engineer who can help migrate the existing Laravel system into a scalable Node.js architecture while keeping the current product logic stable.

Responsibilities:

- Analyze the existing Laravel backend structure, database schema, APIs, and admin workflows.

- Rebuild core backend services using Node.js, preferably TypeScript with NestJS or Express.

- Design clean REST APIs for the mobile app, admin panel, media upload, user accounts, events, venues, and recommendation feed.

- Integrate with existing services including MySQL/PostgreSQL, Redis, object storage, and the recommendation service.

- Support event-based recommendation logic for photos and GIFs, including event ID, venue location, match phase, audience type, media quality, freshness, and popularity.

- Build background jobs for media processing, metadata sync, recommendation data sync, and interaction tracking.

- Set up Docker-based deployment and production-ready environment configuration.

- Improve backend performance, security, logging, monitoring, and maintainability.

- Work closely with the founder/product owner to turn the current Laravel backend into a scalable Node.js backend.

Requirements:

- Strong experience with Node.js backend development.

- Good knowledge of TypeScript, NestJS or Express.js.

- Experience working with Laravel/PHP projects and backend migration is highly preferred.

- Strong understanding of REST API design, authentication, database modeling, and queue-based systems.

- Experience with MySQL or PostgreSQL, Redis, Docker, and Linux server deployment.

- Ability to read an existing codebase and migrate features without breaking current product behavior.

- Experience with media platforms, recommendation systems, feeds, image/video processing, or event-based products is a plus.

Nice to have:

- Experience with Qdrant, Faiss, vector search, recommendation systems, or AI-powered media tagging.

- Experience with cloud storage, CDN, image optimization, and large-scale media upload.

- Experience with sports, concert, creator, or community platforms.

This role is suitable for someone who can work independently, communicate clearly, and help us move from a Laravel MVP backend to a more scalable Node.js backend architecture.