Software Engineer – NestJS & Backend Architecture

Quantic; West Chester (Chester County); On-site; USD 140,000 - 190,000; Full time

Benefits offered by this job

Dental insurance

Health insurance

Paid time off

Vision insurance

Employee stock plans

Job summary

Quantic is seeking a Senior Software Engineer to join the POS Platform team in Exton, PA. You will design and scale core backend microservices and APIs powering our POS ecosystem, focusing on low-latency transaction processing, payment gateway integrations, and real-time data sync for retail and restaurant environments.

The role requires strong NestJS/TypeScript skills, experience with distributed systems, and a track record in fintech/POS domains.

Qualifications

• Backend experience with NestJS, Node.js, and TypeScript (2+ years).
• POS/fintech domain experience strongly preferred.
• Relational (PostgreSQL/MySQL/SQL Server) and NoSQL (MongoDB) skills.
• Messaging/microservices with RabbitMQ/Kafka or NestJS Microservices.
• Cloud (AWS/Azure), Docker, Kubernetes, CI/CD familiarity.
• Testing and security focus: Jest, OAuth2/JWT, rate limiting.

Responsibilities

• Design, build, and maintain high-throughput backend services with NestJS/TypeScript.
• Develop RESTful and GraphQL APIs, WebSockets, and webhooks.
• Design distributed architectures for fault tolerance and sync.
• Optimize PostgreSQL/MySQL/SQL Server, MongoDB and Redis performance.
• Ensure code quality with DI, OOP, DDD and Jest tests.
• Collaborate with DevOps to deploy on AWS/Azure with Docker/Kubernetes and CI/CD.
• Participate in Agile ceremonies and translate requirements into architecture.

Skills

NestJS

Node.js

TypeScript

PostgreSQL

MongoDB

Redis

Docker

Kubernetes

AWS

Azure

GraphQL

RESTful APIs

JWT/OAuth2

Tools

Docker

Kubernetes

GitHub Actions

GitLab CI

Jest

Supertest

Job description

We are seeking a highly motivated Senior Software Engineer specializing in NestJS and TypeScript to join the Quantic POS Platform team. In this role, you will lead the design, development, and scaling of core backend microservices and APIs that power our next-generation Point of Sale (POS) ecosystem. You will architect low-latency transaction processing systems, payment gateway integrations, and real-time data sync modules for retail and restaurant environments. If you are passionate about building resilient distributed systems using modern Node.js/NestJS frameworks in a fast-paced fintech/POS domain, this role is for you.

*** This is a 100% onsite role in our Exton office. No remote or hybrid work ***

Responsibilities

• NestJS & Node.js Core Development: Design, build, and maintain high-throughput, modular backend services using NestJS and TypeScript across the Quantic POS platform.
• API & System Integration: Develop secure RESTful and GraphQL APIs, WebSockets, and webhooks to power hardware terminals, mobile POS applications, online ordering systems, and third-party payment gateways.
• Distributed Architecture: Design and optimize distributed systems for fault tolerance, offline-online data synchronization, and high availability during peak transaction volumes.
• Database & Performance Optimization: Architect and optimize query performance across relational (PostgreSQL) and NoSQL/Caching layers (Couchbase, Redis) for sub-second POS checkout pipelines.
• Code Quality & Testing: Maintain clean code standards using NestJS dependency injection, object-oriented design (OOP), domain-driven design (DDD), and automated testing suites (Jest, Supertest).
• Cloud & DevOps Alignment: Collaborate with DevOps teams to deploy microservices on cloud infrastructure (AWS/Azure) utilizing Docker, Kubernetes, and automated CI/CD pipelines.
• Agile Collaboration: Participate actively in Agile ceremonies, translating complex POS product requirements into scalable technical architecture and actionable technical specs.

Experience & Qualifications

• Backend Expertise: 2+ years of software engineering experience with deep specialization in NestJS, Node.js, and TypeScript.
• POS & Fintech Domain Knowledge: Prior experience with Point of Sale (POS), payment processing/PCI compliance, order management, or high-concurrency transaction platforms is strongly preferred.
• Data Management: Advanced knowledge of relational databases (PostgreSQL, MySQL, SQL Server), NoSQL solutions (MongoDB), and in-memory stores (Redis) for real-time state management.
• Messaging & Microservices: Hands-on experience with microservices architecture, event-driven systems, and message brokers (RabbitMQ, Kafka, or NestJS Microservices).
• Cloud & Infrastructure: Familiarity with AWS or Azure services, Docker containerization, and modern CI/CD tools (GitHub Actions, GitLab CI).
• Testing & Security: Proficiency with unit/integration testing frameworks (Jest) and secure API design practices (OAuth2, JWT, rate limiting).
• Development Methodology: Proven experience operating in Agile/Scrum environments using Git workflow tools (GitHub).

Benefits: Qualified and exceptional candidates will be eligible for our future employee stock plans to be part of the company’s growth.

Other Benefits

• Dental insurance
• Health insurance
• Paid time off
• Vision insurance