Blockchain Backend Engineer

Senior Blockchain Developer

Location: India, Remote

Employment Type: Full-Time / Contract

Department: Engineering

About Us

OpenAssets is building open standards for the next generation of capital markets, providing the trusted foundation for real-world asset tokenization and digital currencies.

We specialize in alternative asset digitization, offering regulatory-conscious tools to design, issue, and manage digital assets in complex financial environments. We also develop loyalty solutions that turn customer engagement into programmable digital assets, helping brands create personalized experiences that drive growth.

OpenAssets operates at the intersection of finance, technology, and regulation focused on building secure, scalable, and open infrastructure for the future of digital markets. Join OpenAssets and be part of shaping the future of digital finance!

Overview

We are seeking a Blockchain Developer to lead the technical implementation of our Web3 infrastructure. In this role, you will be responsible for the end-to-end lifecycle of smart contracts and their integration into our broader financial ecosystem. You will act as a technical authority on blockchain security, scalability, and architecture, ensuring our platform meets the rigorous demands of institutional digital finance.

What You’ll Do

Smart Contract & Blockchain Development

• Design, develop, test, and deploy smart contracts and blockchain applications.
• Build and maintain secure, scalable backend services for blockchain products.
• Develop and maintain cross-platform applications that integrate with on-chain infrastructure.
• Integrate wallets, payment systems, and blockchain APIs with existing systems.
• Optimize for gas efficiency, transaction latency, reliability, and scalability.

Security & Quality

• Implement and uphold best practices for blockchain security and smart contract auditing.
• Review smart contracts and backend code for security vulnerabilities and performance issues.
• Support audits, security reviews, and production releases.
• Maintain high test coverage and disciplined release processes.

Collaboration & Communication

• Collaborate with product and engineering teams to define and deliver technical requirements.
• Communicate technical concepts clearly to both technical and non-technical stakeholders.
• Mentor junior engineers and contribute to a strong engineering culture.
• Stay current with emerging blockchain technologies, DeFi, and Web3 infrastructure trends.

Qualifications & Experience

• Experience: 3+ years of software engineering experience with at least 3+ years of hands-on blockchain/Web3 development.
• Blockchain Core: Strong experience with Solidity and EVM-compatible chains (Ethereum, Polygon, and others).
• Production Deployment: Proven track record building, testing, deploying, and maintaining smart contracts in production.
• Deep Technical Knowledge: Solid understanding of blockchain architecture, including consensus mechanisms, gas optimization, wallet flows, token standards, and transaction lifecycles.
• Full-Stack Proficiency: Good understanding of the MERN stack (MongoDB, Express.js, React, Node.js) and how full-stack applications integrate with blockchain infrastructure.
• Backend Expertise: Proficiency in Node.js and TypeScript with experience building RESTful backend applications.
• Testing & Tooling: Experience with smart contract and backend testing frameworks (e.g., Foundry, Hardhat, Mocha, Jest) and Web3 libraries like Ethers.js or Web3.js.
• Cloud Infrastructure: Hands-on experience with AWS, including deploying, managing, and scaling services like EC2, S3, Lambda, and RDS.
• Databases & DevOps: Comfortable with relational (PostgreSQL) and non-relational (MongoDB) databases, Git, and collaborative development workflows.
• Soft Skills: Strong communication skills in English with the ability to articulate technical concepts to diverse stakeholders.

Nice to Have

• Familiarity with the Move language (Sui, Aptos).
• Experience with smart contract audit tooling such as Slither, Mythril, or Manticore.
• Exposure to RWA tokenization, DeFi, stablecoins, NFTs, staking, or bridging protocols.
• Professional background in fintech, payments, or regulated blockchain use cases.

We are committed to providing equal opportunity for qualified applicants to contract positions, regardless of race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or veteran status. This is a contract opportunity, not a direct employment role.

What role will you play? 

As a Full Stack Engineer, you will play a pivotal role in our development team, bridging the gap between the visual elements and the server-side infrastructure. You will be instrumental in developing full-fledged, scalable applications by combining the art of design with the science of programming. With your expertise in both front-end and back-end technologies, you will ensure the entire stack is designed and built for speed and functionality.  

Your day to day will involve designing and developing dynamic, high-quality web applications, leveraging the Node.js and python for the back end services and React/Angular for the front end. Close collaboration with UI/UX designers will be essential, allowing you to bring web designs to life while ensuring high performance and responsiveness. Additionally, you will actively participate in coding, debugging, and testing to deliver reliable solutions whilst also working closely with other developers, designers, and product managers, fostering a collaborative environment to meet project goals and deadlines effectively. 

What you offer 

• Proficiency in Typescript and a good understanding of React  
• Solid experience with the Node.js, including the ability to develop RESTful APIs 
• Experience with containerisation of service using Docker 
• Knowledge of modern authorisation mechanisms, such as JSON Web Token (JWT)  
• Familiarity with SQL databases, such as PostgreSQL 
• Experience with Kafka or other event driven tools and tech 
• Nice to have some experience integrating with LLMs through open AI, Gemini etc. 
• Nice to have exposure to AI tooling – Claude, Copilot, Cursor etc. 
• AWS experience is a nice to have 

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.

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.

Role Overview

We are looking for a Senior Full Stack Developer to build and scale our fintech platform. You will own the entire lifecycle of our financial products, from designing high-performance relational schemas in PostgreSQL to building interactive dashboards in React.

Key Responsibilities

• Full Stack Development: Build and maintain end-to-end features using the PERN stack

(PostgreSQL, Express.js, React, Node.js).

• Database Optimization: Design complex relational models and optimize SQL queries to

handle high-volume financial data and audit trails.

• Security & Compliance: Implement rigorous security measures (e.g., JWT, OAuth, data

encryption) and ensure the platform adheres to fintech standards like PCI-DSS.

• API Architecture: Develop robust RESTful APIs to integrate with third-party banking APIs,

payment processors (Stripe/Plaid), and KYC providers.

Technical Requirements

• Front-end: Advanced proficiency in React.js (Hooks, Context API, Redux or TanStack Query)

and modern CSS (Tailwind/Styled Components).

• Back-end: Expert-level Node.js and Express.js experience, with a focus on asynchronous

programming and secure API design.

• Database: Deep knowledge of PostgreSQL (complex joins, indexing, triggers, and

migrations).

Additional skills

• Understanding of Event-Driven Architecture (using AWS SQS/SNS or Kafka).

• Familiarity with SOC2 or ISO 27001 compliance frameworks.

• Cloud (AWS): Proven experience with:

• RDS/Aurora for managed databases.
• IAM for secure access management.
• AWS Lambda & API Gateway for serverless architecture.
• CloudWatch for monitoring and alerting.

• Tools: Git, Docker, and experience with CI/CD workflows.

About US

RJ Fintech Solutions Pvt. Ltd. is a high-growth fintech startup on a mission to automate business financial operations. In a world where financial systems are often slow and opaque, we are building the "missing link"—a secure, transparent, and lightning-fast platform that puts banking and compliance first for various corporates.

We are not just another financial app; we are an engineering-first company. We believe that elegant code and robust architecture are the foundations of trust. By leveraging the PERN stack and AWS cloud-native infrastructure, we are replacing legacy complexity with modern, scalable solutions.

Why Work With Us?

1. Build the Foundation, Not Just Features

You won't be a small cog in a massive machine. As an early member of our engineering team, you will help define our technical architecture, choose our libraries, and set the coding standards for everyone who follows. Your fingerprints will be on the core DNA of our product.

2. Solve Problems That Matter

Fintech is one of the few industries where code has a direct, measurable impact on people's lives.

Whether we are [e.g., simplifying cross-border payments, democratizing investment, or building the next generation of credit], you will be solving high-stakes challenges around security, trust, and financial inclusion.

Full stack Developer (Ref.ID: VRPL-FSD-Chn-0326)

No. of Positions: 2 Nos. Senior 1 No. Junior 1 No.

API Development & Architecture:

Design and develop scalable RESTful APIs using Node.js & TypeScript

Build modular, reusable, and clean backend architecture

Implement authentication & authorization (JWT / OAuth / Role-based access)

Ensure API security best practices

Write well-structured documentation (Swagger / Postman)

Real-Time Communication (Sockets):

Develop real-time features using WebSockets / Socket.io

Implement:

Live tracking

Real-time notifications

Status updates

Chat systems

Optimize socket performance and reconnection handling

Ensure scalability under concurrent user load

Database & Data Layer (PostgreSQL):

Design scalable and optimized database schemas

Write complex SQL queries & joins

Implement indexing & query optimization

Handle transactions and concurrency control

Work with ORMs like Prisma / TypeORM (preferred)

Maintain database security and backup strategies

Ensure data security and backups

Performance & Scalability:

Optimize API response times

Implement caching strategies (Redis preferred)

Design rate limiting and throttling mechanisms

Ensure system reliability & fault tolerance

Handle background jobs & queues

Deployment & DevOps Collaboration:

Deploy applications on AWS / GCP

Work with Docker containers

Implement CI/CD pipelines

Monitor logs & performance metrics

WhatsApp Business Integration:

Integrate WhatsApp Business API (Cloud / On-Premise)

Work with providers like Exotel / Twilio (preferred)

Implement Template messaging

OTP authentication

Notifications & alerts

Two-way communication

Manage webhook events and delivery tracking

Ensure compliance with WhatsApp policies

Required Skills:

Strong proficiency in Node.js

Hands-on experience with TypeScript

Strong experience in PostgreSQL

Experience building RESTful APIs

Experience with WebSockets / Socket.io

Good understanding of system design & architecture

Git version control

Knowledge of API security best practices

Preferred Skills:

Experience in real-time platforms (ride-hailing, delivery, chat systems)

Redis for caching

Message queues (Kafka / RabbitMQ / BullMQ)

Microservices architecture

Payment gateway integration

Cloud infrastructure knowledge

Soft Skills:

Strong analytical, problem-solving skills, and debugging skills

Startup mindset & ownership attitude

Ability to work in fast-paced startup environment and work independently

Good communication skills in all aspects

About AimInfologics

AimInfologics is a software development company based in Gujarat, India. We build mobile apps, web platforms, SaaS products, AI integrations, automation systems, and custom software solutions for clients in India and international markets.

We are looking for a Full Stack Developer who has strong hands-on experience with Node.js and Next.js and can work on real client projects with ownership.

Role: Full Stack Developer – Node.js & Next.js

Job Type: Full-time

Location: Ahmedabad, Gujarat / On-site

Experience: 2–5 years preferred

Salary: As per experience and practical skill level

Role Description :

The selected developer will work on web applications, admin panels, APIs, SaaS platforms, CRM systems, dashboards, and AI-integrated software products.

This role is suitable for someone who can handle both frontend and backend work, understand requirements properly, write clean code, debug issues, and deliver features with proper quality.

We are not looking for someone who only knows basic tutorials. We need someone who has worked on real projects and can take responsibility for modules independently.

Key Responsibilities

• Develop and maintain web applications using Next.js

• Build backend APIs using Node.js and Express.js

• Work with MongoDB and database-driven application logic

• Create clean, responsive, and user-friendly frontend screens

• Integrate third-party APIs, payment gateways, AI APIs, CRM tools, and cloud services when required

• Write clean, reusable, and maintainable code

• Debug bugs, performance issues, and production-level problems

• Coordinate with UI/UX designers, backend developers, mobile developers, and project managers

• Understand client requirements and convert them into working features

• Use Git properly for code management and team collaboration

• Deploy or support deployment on platforms such as Vercel, AWS, or similar environments

Required Skills

• Strong experience with Node.js

• Strong experience with Next.js and React.js

• Good knowledge of JavaScript and TypeScript

• Experience with MongoDB and database design basics

• Good understanding of REST APIs

• Experience with Express.js or similar backend frameworks

• Ability to integrate third-party APIs

• Good understanding of authentication, authorization, JWT, roles, and permissions

• Basic understanding of cloud deployment, Vercel, AWS, Nginx, or PM2 is a plus

• Good debugging and problem-solving skills

• Ability to write clean and structured code

• Basic understanding of UI/UX and responsive design

• Good communication and team coordination skills

Good to Have

• Experience with AI API integrations such as OpenAI or similar tools

• Experience with payment gateways

• Experience with SaaS, CRM, ERP, dashboards, or admin panel development

• Experience with server deployment and production issue handling

• Experience working with international client projects

Who Should Apply

Apply only if you are serious about full-time work and can take ownership of development tasks.

This role is best for someone who wants to grow as a strong full stack developer and work on real business applications, SaaS products, AI-based systems, and international client projects.

Hiring Process

1. Profile screening
2. Technical interview
3. Practical task / code review
4. Final discussion

While applying, please mention:

• Your total experience

• Projects you have worked on using Node.js and Next.js

• Current salary

• Expected salary

• Notice period

• GitHub / portfolio link, if available

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.

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!

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.