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 strong R&D; setting, 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 using
NestJS
, with full
OpenAPI/Swagger
documentation.
Implement secure
JWT-based authentication
with access/refresh tokens using HTTP-only cookies.
Define and validate
DTOs
with NestJS validation pipes for type-safe request/response contracts.
Configure
CORS policies
,
rate limiting
(e.g., 40 requests/min/user), and comprehensive request logging.
Maintain backward-compatible
API versioning
, planning for future iterations.
Asynchronous Processing & Job Queues
Architect and maintain
BullMQ
queues 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
Design
normalised PostgreSQL schemas
with proper relationships, constraints, and indexing.
Use
TypeORM
for 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 with
Google Cloud SQL
for high availability, backups, and disaster recovery.
Cloud & Infrastructure Integration
Integrate with
Google Cloud Storage
for secure file handling.
Manage
Redis
connections for BullMQ job persistence.
Design
event-driven systems
using
Google 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 on
Google Cloud Run
with auto-scaling, health checks, and zero-downtime updates.
Build
serverless 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.js
applications.
Good knowledge using
Javascript
Develop reusable UI components, manage state (Redux, Zustand, or Context API), and integrate backend APIs efficiently.
Implement
real-time updates
with WebSockets for job tracking and notifications.
Collaborate with designers to create
pixel-perfect, accessible interfaces
using
Tailwind CSS
and
shadcn/ui
.
Optimise performance: code splitting, lazy loading, and bundle size reduction.
Implement
form validation
with React Hook Form and Zod, and efficient server state management via
React Query
.
Build interactive
data visualisations
for analytics and reporting
Experience working with
machine 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 codematix.com.au

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