Java 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

About the Role:

We are seeking a skilled Java Developer to join our team. The ideal candidate will have strong experience in core Java development along with exposure to modern frameworks and tools. You will be responsible for designing, developing, and maintaining scalable applications while ensuring performance, security, and code quality.

Key Responsibilities:

• Design, develop, test, and maintain Java-based applications.
• Write clean, efficient, and reusable code following best practices.
• Collaborate with cross-functional teams (Product, QA, DevOps, etc.) to deliver high-quality software.
• Troubleshoot, debug, and optimize application performance.
• Participate in code reviews and contribute to continuous improvement.
• Stay updated with emerging trends, tools, and technologies in the Java ecosystem.

Required Skills & Qualifications:

• Strong proficiency in Core Java (Java 8/11/17).
• Experience with frameworks such as Spring / Spring Boot / Hibernate.
• Good knowledge of REST APIs, Microservices architecture.
• Familiarity with SQL/NoSQL databases (MySQL, PostgreSQL, MongoDB, etc.).
• Understanding of multithreading, collections, and design patterns.
• Experience with version control systems (Git) and build tools (Maven/Gradle).
• Solid problem-solving skills and ability to work in an Agile environment.

Good to Have:

• Exposure to cloud platforms (AWS, Azure, GCP).
• Knowledge of containerization (Docker, Kubernetes).
• Experience with messaging systems (Kafka, RabbitMQ).
• Familiarity with CI/CD pipelines.

We are looking for a Software Development Engineer (Java Backend) to join our team! As a key member of our engineering team, you will be responsible for the end-to-end development and delivery of our products.

Diverse Hiring: SDE 3 (Java Backend) | 5-8 Y | Bangalore WFO | Females Only |

Prefer qualified candidates from Premium Institutes - NIT / IIT / IIIT / REC / BITS / REC with relevant working from Products / Unicorns alike Flipkart, Amazon, CRED, Swiggy, Zomato, Jupiter, Blinkit, OYO, Ola, Uber, Pine Labs, PayTM,

Scope Of Work:

Design, develop, deliver & maintain highly-scalable, cloud-native products, working with product and design teams.

Ability to ship to production in small testable pieces of code, in quick iterations

A good grasp of scalable software development, with a DevOps mindset

Providing people and technical leadership to your engineering teams

Support in developing and managing companies IT infrastructure

Participate in the hiring of world-class engineers and grow the engineering team

Required Skills & Qualifications:

Must have a deep understanding of both development and operations processes, as well as a strong technical background.

5+ years of experience developing software products - Java.

Demonstrable experience in leading software teams by example.

Java, Java8, Springboot, Microservices, core java, j2ee, JAVA, Springboot

backend, core java, java8, micro services

7+ years of experience with Design, development & architecture.

• Experience in software development with minimum 3 plus years of architecture experience.
• Experience in Core JAVA 8
• Experience in Java J2EE, Microservices
• Experience in Java - Spring, Java - SpringBoot, GCP , Hibernate,JDBC
• Experience in Multi-threading, Performance and Scaling is a plus
• Have used the RDBMS and NoSQL databases like MySQL/Oracle, MongoDB, Cassandra, Neo4J Risk for production ready software’s
• Cloud Native application design experience is a plus
• CICD – Release Pipeline experience
• Experience in application of principles of Architecture Design
• Experience building large scale, high performance distributed systems
• Strong understanding of modern development techniques and processes such as Dev Ops /Cloud
• Promoter of Agile/Scrum, TDD and CI/CD best practices
• Analyzes, designs, programs, debugs and modifies software enhancements and/or new products used in local, networked or Internet-related computer programs. (Code must be used in core version of applications available for sale commercially.)
• Interacts with Delivery managers and/or users to define system requirements and/or necessary modifications.
• Participates in software design meetings and analyzes user needs to determine technical requirements.
• Write technical specifications based on conceptual design and stated business requirements.
• Writes code, completes programming and performs testing and debugging of applications using current programming languages and technologies.
• Completes documentation and procedures for installation and maintenance.
• Trains and communicates with internal Client Training, Client Relationship and Sales teams on systems application.
• May be responsible for developing or executing project plans, budgets and schedules and for documenting work and results.
• May deliver informational and decision-seeking presentations to technical and business groups to internal and/or external audiences.

About the company, Kuants is a fintech startup offering products in the Wealth tech space. We are the market leaders in Algo trading software and 

We are looking for a Back-End Web Developer responsible for managing the interchange of data between the server and the users. Your primary focus will be the development of all server-side logic, definition, and maintenance of the central database, and ensuring high performance and responsiveness to requests from the front-end. You will also be responsible for integrating the front-end elements built by your coworkers into the application. A basic understanding of front-end technologies is therefore necessary as well.

Responsibilities

• Integration of user-facing elements developed by 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

• 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
• User authentication and authorization between multiple systems, servers, and environments
• 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
• Data migration, transformation, and scripting
• Setup and administration of backups
• Outputting data in different formats
• Understanding differences between multiple delivery platforms such as mobile vs desktop, and optimizing output to match the specific platform
• Creating database schemas that represent and support business processes
• Implementing automated testing platforms and unit tests
• Proficient knowledge of a Django, REDIS, MySQL
• Proficient understanding of code versioning tools, such as Git
• Proficient understanding of OWASP security principles
• Understanding of “session management” in a distributed server environment