Job Description
18th September, ****
A leading R&D; company based in Castle Hill are currently seeking a full-stack developer to join their growing engineering team.
You'll be working within a technically robust R&D; environment, developing and supporting software used across the company's products and systems.
The role will involve a mix of front-end and back-end development, working closely with a small team of fullstack devs and AI developers to build reliable, user-friendly applications.
The company are looking for an engineer that's interested in real-world technology and product development, rather than purely web-based projects.
This is a full-time, permanent position which requires you to be onsite in the Castle Hill office.
You must have working rights in Australia to be eligible for this position.
Key Requirements:
Backend Development:
API Development & Architecture
Design, implement, and maintain RESTful APIs usingNestJS, with fullOpenAPI/Swaggerdocumentation.
Implement secureJWT-based authenticationwith access/refresh tokens using HTTP-only cookies.
Define and validateDTOswith NestJS validation pipes for type-safe request/response contracts.
ConfigureCORS policies,rate limiting(e.g., 40requests/min/user),and comprehensive request logging.
Maintain backward-compatibleAPI versioning, planning for future iterations.
Asynchronous Processing & Job Queues
Architect and maintainBullMQqueues for background job processing.
Handle long-running tasks (e.g., floor plan analysis, ML API integration) with retry and exponential backoff strategies.
Monitor queue health, optimise concurrency, and scale processing capacity efficiently.
Database Design & Optimisation
Designnormalised PostgreSQL schemaswith proper relationships, constraints, and indexing.
UseTypeORMfor entities, migrations, and data integrity management.




Optimise queries to prevent N+1 issues and ensure sub-second response times.
Implement transactional consistency for critical multi-step operations.
Work withGoogle Cloud SQLfor high availability, backups, and disaster recovery.
Cloud & Infrastructure Integration
Integrate withGoogle Cloud Storagefor secure file handling.
ManageRedisconnections for BullMQ job persistence.
Designevent-driven systemsusingGoogle Cloud Pub/Sub; implement publish-subscribe patterns, versioned message schemas, and dead-letter handling.
Ensure reliable message delivery (exactly-once / at-least-once semantics) and monitor system metrics.
Deploy containerised microservices onGoogle Cloud Runwith auto-scaling, health checks, and zero-downtime updates.
Buildserverless functions(GCF Gen 2) triggered by HTTP, Pub/Sub, Firestore, or Storage events with proper retry, idempotency, and performance optimisation.
Highly Desirable Skills:
Build responsive,TypeScript-based React.jsapplications.
Good knowledge usingJavascript
Develop reusable UI components, manage state (Redux, Zustand, or Context API), and integrate backend APIs efficiently.
Implementreal-time updateswith WebSockets for job tracking and notifications.
Collaborate with designers to createpixel-perfect, accessible interfacesusingTailwind CSSandshadcn/ui.
Optimise performance: code splitting, lazy loading, and bundle size reduction.
Implementform validationwith React Hook Form and Zod, and efficient server state management viaReact Query.
Build interactivedata visualisationsfor analytics and reporting
Experience working withmachine learning and AI
This role is fully onsite in Castle Hill and requires you to already hold a valid working visa in Australia.
Sponsorship is not provided.
Codematix is a recruitment agency.
You can find out more about Codematix by visiting

📌 Senior Full-Stack Developer (New South Wales)
🏢 Codematix
📍 New South Wales