MERN Stack Developer

Experienced Senior Full Stack Engineer to Build & Backend for Event Ticketing Platform Using Claude Code

Overview

We have the frontend already built in Replit for both user and admin experiences. We are looking for a very experienced software engineer to design, build, and scale a production ready backend for a high concurrency event ticketing platform.

This role is for a true senior engineer who actively uses Claude Code as part of their daily development workflow, understands how to review and harden AI assisted output, and can ship systems that hold up under real world load, QA, and security testing.

This is not a prototype or demo system. This backend must be reliable, scalable, secure, and extremely well documented.

What You Will Be Building

• Backend services for an event ticketing platform

• Multi tenant architecture supporting thousands of organizers and events

• High concurrency purchase and checkout flows

• Secure user, admin, and system level access controls

• Production deployments with secrets management, middleware, and security layers

• Observability, logging, and metrics suitable for QA and load testing

• A thoroughly documented backend that future engineers can onboard into quickly

Core Engineering Requirements

• 10 plus years of professional software engineering experience

• Expert level experience using Claude Code or equivalent AI coding agents in real production workflows

• Deep experience building backends with Node.js

• Strong experience with Supabase and PostgreSQL

• Experience deploying and scaling applications on Vercel

• Proven experience extending existing codebases safely

• Strong API design and database performance fundamentals

• Ability to reason clearly about concurrency, transactions, and failure modes

Scalability and Performance Expectations

The backend must be designed to support:

• Hundreds of thousands of ticket purchases

• Thousands of concurrent users and tenants

• Large traffic spikes during on sale windows

• Load testing across all major latency percentiles including p90, p95, and p99

• Extremely low tail latency under high concurrency

• Graceful degradation and recovery under stress

You should be comfortable designing and implementing caching strategies, queue based workflows, idempotent operations, locking mechanisms, and transactional safety.

Security and Production Readiness

You must be able to:

• Set up production environments with proper secrets management

• Implement middleware for authentication, authorization, and rate limiting

• Design secure communication between frontend and backend

• Apply industry best practices for security hardening

• Prepare the system to pass penetration testing

• Maintain clean separation of concerns and least privilege access

Documentation and Developer Experience Requirements

High quality documentation is a hard requirement for this role.

You must have experience:

• Using AI powered documentation tools to generate and maintain technical documentation

• Producing clear architectural overviews and system diagrams

• Writing detailed README files and onboarding guides

• Documenting APIs, data models, and critical flows

• Keeping documentation in sync with code changes over time

We expect the backend to be easy to understand, easy to extend, and well explained for future engineers.

How We Evaluate Candidates

We are looking for engineers who can demonstrate:

• Real production systems they have built or scaled

• Clear judgment in how they use Claude Code and validate AI generated output

• Strong opinions on production readiness backed by experience

• The ability to move fast without sacrificing quality or safety

A short paid technical task may be used that involves real backend work with production quality code and documentation.

LendFlow is an AI-powered home loan assessment platform that helps mortgage brokers and lenders save hours by automating document analysis, income validation, and serviceability assessment. We turn complex financial documents into clear insights—fast.

We’re building a smart assistant that ingests client docs (bank statements, payslips, loan summaries) and uses modular AI agents to extract, classify, and summarize financial data in minutes, not hours. Think OCR + AI agents + compliance-ready outputs.

🛠️ What You’ll Be Building

As part of our early technical team, you’ll help us develop and launch our MVP. Key modules include:

• Document ingestion and OCR processing (Textract, Document AI)
• AI agent workflows using LangChain or CrewAI
• Serviceability calculators with business rule engines
• React + Next.js frontend for brokers and analysts
• FastAPI backend with PostgreSQL
• Security, encryption, audit logging (privacy-first design)

🎯 We’re Looking For:

Must-Have Skills:

• Strong experience with Python (FastAPI, OCR, LLMs, prompt engineering)
• Familiarity with AI agent frameworks (LangChain, CrewAI, Autogen, or similar)
• Frontend skills in React.js / Next.js
• Experience with PostgreSQL and cloud storage (AWS/GCP)
• Understanding of financial documents and data privacy best practices

Bonus Points:

• Experience with OCR tools like Amazon Textract, Tesseract, or Document AI
• Building ML/NLP pipelines in real-world apps
• Prior work in fintech, lending, or proptech sectors

• Experience in building reusable, and modular UI components and ensure cross browser compatibility.
• 3+ years developing, deploying, and supporting web applications built on framework. like Django/ NodeJS/ ReactJS.
• Must have 3+ years of current experience in Python or Go
• Knowledge in writing automated tests
• Proficient in High Level Systems Integration Design
• Understanding of Accessibility and internationalization
• Proficient in source control using GitHub
• Experience with building and maintaining a SaaS product at scale
• Write code that is tested and testable and you take responsibility for the quality of the code you produce. You will be helping build the best user experience for our Anaplan platform.
• Work in a hybrid cloud infrastructure, considering the implementation of functionality through several distributed components and services.
• Express your positive energy and enthusiasm - cultural fit is a really big deal for us. we're looking for really committed people who love solving big problems and are self-motivated to get things done.
• Familiar with developing SaaS applications using Django, NodeJS, ReactJS for development, be an added plus.

• Ability to translate Wireframes and PSD Designs into functional web apps using HTML5, AngularJS, React , Node.js, and Mongo, Dynamo
• With 3+ years, Proven experience as a Full Stack Developer or similar role preferably using MERN stack.
• Binding of UI elements to JavaScript object models
• Creating RESTful services with Node.js
• Architect scalable web architectures
• Work in a cross-functional team to deliver a complete user experience
• Create Unit and Integration tests to ensure the quality of code
• Be responsive to change requests and feature requests
• Write code that is cross-platform and cross-device compatible
• Ability to wear many hats and learn new technologies quickly
• Experience in using AWS

• Minimum of 1-2  years of experience as a Full Stack Developer or similar role.
• Bachelor’s degree in Security, Computer Science, or a related field.
• Experience with  React.js, Node.js, Next.js, and JS libraries.
• Must have an understanding of web3 and blockchain fundamentals.
• An exceptional understanding of secure and scalable application development, including the full lifecycle of API microservices services, including authentication, API gateways, and versioning.
• Excellent analytical and time management skills.
• Ability to wear many hats and learn new technologies quickly.
• Solid knowledge of web architecture and design patterns.
• Good knowledge and understanding of Backend and Frontend technologies
• Hands-on experience in building REST API using NodeJs
• Excellent communication and teamwork skills
• Great attention to detail.

• Demonstrated experience as a software engineer, with at least 8+ years’ experience in technology roles
• Experience working on complex systems and cloud architectures, preferably in a B2B or enterprise context
• Significant experience with the Java programming language and frameworks such as Spring & SpringBoot
• Good working experience with front-end Javascript frameworks such as ReactJS
• Experience optimizing databases and SQL queries for high-performance 
• Good knowledge of AWS services, design patterns and practices - ideally certified
• Experience and keen understanding of the value of working in agile teams
• A “quality-first” mindset, with experience working in continuous integration environments
• Highly effective at communicating, and comfortable whiteboarding design ideas with teams of engineers, product managers, and business analysts
• Desire to challenge the status quo and maturity to know when to compromise
• Respect for other team members and a highly collaborative approach to working and learning together

Skillset

Angular2+

Node.js

RESTfull API integration

Experience working with Docker and containerized applications

Experience working with Kubernetes or other container orchestration tools

Knowledge and understanding of working in AWS environments

Experience in full-stack development (with a passion)

RDBMS and Document Database

Experience with Agile/Scrum Development Methodology

Exposure to Continues Integration (CI/ CD)

Version control systems like Git/ TFS

( For SSE level this is mandatory)

• Developer testing
• Code review
• Requirement handling