CastleSoft – Smarter decisions with AI you can trust

What We Do

We design and build AI-powered software in C# and .NET, from AI agents and business applications to immersive experiences, for organisations that need it secure, private and built to last.

CastleSoft AI

AI agents and agentic workflows built in C# and .NET, with secure, governed deployment and an Australian-only processing option.

CastleSoft Health

Intelligent software that streamlines healthcare administration, revenue cycle management and patient data analysis.

CastleSoft Studios

Interactive applications, games and AR/VR experiences for education, training and entertainment.

Your Data Can Stay in Australia

On request, we process data in Australia, using AI models that run locally on Apple silicon or, where more powerful commercial models are needed, de-identifying the information in Australia first.

Learn about Australian-only processing

Built on the Right Foundations

AI-first. Engineered in C#. We combine .NET, agentic AI and cloud platforms to build practical software—from business applications to immersive experiences and connected devices.

C# & Cloud Engineering

The foundation for our applications, APIs, data and cloud services.

C# / .NET
ASP.NET Core
Blazor
SharpCoreDB
Aspire
Microsoft Azure
AWS
Google Cloud

Agentic AI

Specialist agents, connected tools and model-powered workflows.

Microsoft Foundry
Microsoft Agent Framework
Microsoft.Extensions.AI
Semantic Kernel
MCP
Anthropic Claude & OpenAI
OpenRouter
Local LLMs (Apple silicon)

Spatial & Interactive

Interactive applications and immersive experiences.

Godot
Unity
Apple ARKit
RealityKit
Core ML

Embedded & Edge

C# development for connected devices and embedded systems.

.NET nanoFramework

Supported Platforms: 29
Years in Business: 30+
Active Users: 10,000+
Offices: 2

About CastleSoft

Founded in Newcastle, Australia, in 1995 by Andrew Tierney, CastleSoft has spent more than 30 years building software for government, defence, finance, mining, education, health and small business.

Today we are a founder-led, AI-first business: Andrew leads a coordinated team of specialist AI agents, with human oversight for critical decisions, and privacy built into everything we do.

About CastleSoft Meet our team