Principal Backend Engineer

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.

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.

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 VerbaFlo.ai

VerbaFlo.ai is a fast-growing AI SaaS startup revolutionizing how businesses leverage AI-powered solutions. As a part of our dynamic team, you’ll work alongside industry leaders and visionaries to drive innovation and execution across multiple functions.

Role Overview

We are looking for a Senior Backend Engineer to design and develop user-friendly, scalable, and high-performance web applications. This role requires deep expertise in backend technologies, attention to detail, and the ability to collaborate with cross-functional teams.

Responsibilities

• Design, develop, and maintain scalable backend systems, APIs, and data pipelines.
• Collaborate closely with frontend engineers, product managers, and AI teams to deliver cohesive features and seamless user experiences.
• Ensure the reliability, security, and performance of backend systems.
• Write clean, maintainable, and efficient code using modern backend practices.
• Implement automated testing, CI/CD workflows, and infrastructure as code (where applicable).
• Own the end-to-end lifecycle of backend features, from architecture to deployment.
• Monitor production systems and resolve performance and scalability issues.
• Contribute to architectural decisions and help evolve our engineering best practices.

Requirements

• 4–6 years of experience in backend development in startups, preferably in SaaS or AI-driven products.
• Proficiency in Node.js, Python, or Go
• Deep understanding of RESTful API design.
• Strong experience with databases: PostgreSQL, MongoDB, ElasticSearch.
• Exposure to message queues, job schedulers, or event-driven architectures (e.g., SQS, Celery, etc).
• Familiarity with cloud platforms like AWS, GCP, or Azure and containerization tools (Docker, Kubernetes).
• Experience with Git, CI/CD tools, and writing unit/integration tests.
• Strong problem-solving skills and a mindset geared toward performance and security.
• Excellent communication and collaboration abilities.

Why Join Us?

• Work directly with top leadership in a high-impact role.
• Be part of an innovative and fast-growing AI startup.
• Opportunity to take ownership of key projects and drive efficiency.
• A collaborative, ambitious, and fast-paced work environment.
• Perks & Benefits: gym membership benefit, workation policy, and company-sponsored lunch.

If you’re looking for an exciting role that combines strategy, execution, and leadership exposure, we’d love to hear from you!

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.

Strong Backend Node.js Developer Profile

2

Mandatory (Experience 1) – Must have 7+ years of hands-on Backend Engineering experience using Node.js building production-grade systems for B2C products at meaningful consumer scale

3

Mandatory (Experience 2) – Must be AI-native in their own engineering workflow: already uses LLMs and agentic tooling across the SDLC, from design and code generation through testing and debugging

4

Mandatory (Experience 3) – Must have owned backend architecture end to end, including greenfield builds. Should be able to make early architecture calls and reason clearly about service boundaries, data flow, caching, queueing, failure modes, scalability, and reliability trade-offs under real constraints.

5

Mandatory (Experience 4) – Must have a solid understanding of backend fundamentals, including API development, service-oriented architecture, data structures, algorithms, and clean coding practices

6

Mandatory (Experience 5) – Must have experience designing, building, and maintaining APIs and backend services, including integrations with external systems and third-party platforms

7

Mandatory (Experience 6) – Must have strong experience working with databases (SQL and/or NoSQL), including efficient data modeling, query optimization, and performance tuning

8

Mandatory (Company) – Must have worked in B2C product companies / startups at meaningful consumer scale. (WealthTech, FinTech, or high-growth consumer product background is highly preferred)

9

Mandatory (Stability) – Must have a stable career history, with consistent tenure across previous companies; frequent job-hopping will not be considered

10

Mandatory (AI Product) – Must have experience building and shipping products that use LLMs and agentic workflows to end users.

11

Mandatory (College) – ) - 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 top-tier product companies

12

Mandatory (Compensation Alignment) – Candidate must be comfortable with the compensation structure where the company matches their current CTC and provides ESOPs, without any salary hike

Required Experience: 10–15 years (with at least 3–5 years in leadership roles)

● 10–15 years of overall experience in backend engineering, with strong exposure to

Python and/or Golang.

● 3–5 years of experience managing engineering teams.

● Proven experience delivering large-scale, distributed systems in production

environments.

● Strong understanding of microservices, cloud-native architecture, and DevOps

practices.

● Hands-on background in backend engineering (able to guide teams technically, even

if not coding daily).

● Familiarity with CI/CD pipelines, observability, and performance optimization.

● Experience in financial services or high-transaction domains is a plus.

● Experience leading teams that have utilized AI-driven development practices (e.g.,

agentic coding, LLM integration) to improve productivity and innovation is a

significant advantage.

Skills

● Excellent leadership and people management abilities.

● Strong communication and stakeholder management skills.

● Ability to balance technical depth with business priorities.

● Problem-solving mindset with a focus on delivery and impact.

● Passion for building engineering culture and improving developer experience.

Senior Backend Engineer

What You'll Do :

- Build and scale the core backend and infrastructure powering a customer feedback intelligence platform - owning systems from data ingestion through real-time analytics.

- Harden ML and NLP infrastructure, including pipelines, model serving, and data flows, so features remain reliable in real-world production environments at scale.

- Own critical infrastructure decisions around data models, event flows, and service boundaries, with strong correctness and data-integrity guarantees.

- Instrument systems deeply for observability, ensuring failures surface early and production behavior becomes a source of continuous learning.

- Balance speed, cost, and long-term system health, making pragmatic, cost-effective trade-offs while shipping continuously.

- Partner closely with Product, Design, and the founding team to turn ambiguous problem statements into clear, scalable infrastructure.

- Raise the engineering bar through clean code, thorough design reviews, mentorship, and platform-level improvements.

What It Takes :

- 6-8 years of software engineering experience, with a proven track record of building and shipping reliable systems in production.

- 3+ years at a single organization where you've built infrastructure from the ground up and owned complex projects end to end.

- Deep expertise in infrastructure, including data pipelines, event-driven and microservices architectures, observability, reliability, and cost optimization.

Tech Stack :

-serverless computing, SQL/NoSQL databases, Elasticsearch, or GraphQL.

Bonus :

- Experience building or operating ML/NLP infrastructure such as data pipelines, model serving, feature stores, or inference systems.

Why This Opportunity :

- High Impact : Build foundational backend and infrastructure systems at an early-stage, high-growth technology company.

- Ownership : Take end-to-end responsibility for critical features, systems, and infrastructure.

- Complex Challenges : Work across ML/NLP infrastructure, distributed systems, data pipelines, and real-time analytics.

- Growth : Deepen your technical expertise while having the opportunity to grow into a technical leadership path.

- Culture : Work in an open, collaborative, and values-driven environment with significant autonomy.

- Benefits : Competitive compensation, equity, hybrid work setup, premium healthcare, and more.

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!

Most sales tools help you send emails. We’re building something different.

At Salesforge, we’re creating autonomous AI agents that can:

Find the right prospects

Generate highly personalized outreach

Run conversations

And book meetings

All without human involvement.

Why this is interesting

A lot of AI products stop at “generate text.” We’re focused on outcomes.

That means solving problems like:

How do you generate messages that actually get replies?

How do you evaluate and improve agent performance over time?

How do you orchestrate millions of AI-driven interactions reliably?

How do you combine structured data + LLMs in a way that scales?

If you enjoy working at the intersection of systems + AI + real-world feedback loops, this will feel like a playground.

What you’ll be working on

You won’t be maintaining legacy systems.

You’ll be:

Designing and building core backend systems that power our AI agents

Creating APIs and services that handle high-scale, real-time workflows

Working with queues (Kafka / SQS / RabbitMQ) to orchestrate async systems

Thinking deeply about performance, cost, and reliability in AI pipelines

Shipping features end-to-end with a small, senior team

The team

We’re a small group of experienced builders. We move quickly, care about quality, and avoid unnecessary process.

No layers of management.

No long planning cycles.

Lots of ownership and autonomy.

What we’re looking for

5+ years of backend engineering experience

Strong system design fundamentals

Experience with distributed systems and async processing

Familiarity with relational and/or document databases

Clear communicator, low ego, high ownership

Why join

You’ll work on a product where the output is measurable (meetings booked, revenue generated)

You’ll have real ownership from day one

You’ll be early in building a new category (AI sales agents)

You’ll grow as fast as we do