Stuart was in the middle of a client build when his AI coding tools got a quiet but significant upgrade. A colleague messaged him asking what actually changed. This is what he said.
Daniel 2:23 PM
Stuart 2:24 PM
01 — The tax nobody talks about
The hidden overhead in custom app development
That was his honest first reaction. Not a feature list. Not a sales pitch. Just a feeling that something had quietly shifted in how the work gets done.
Anyone building custom web applications with AI tools knows the routine. You're working well, making progress, and then the model hits its context limit. It starts forgetting things. It contradicts what it said twenty minutes ago. So you learn to work around it - clearing sessions early, keeping detailed notes, tracking what the model needs to know when you start fresh.
It works. But there's an overhead to all of that, and it quietly eats into every build.
The best results used to come from clearing more often and keeping meticulous documentation flows. Now it just keeps its own context longer.
Stuart Cox, CEO — Northbase
The context window went from 200K tokens to 1M. In practical terms, that's enough to hold an entire production codebase, its documentation, and its test suite in a single session. The model doesn't need reminding what it's working on. It's all already there.
02 — What changed
A different kind of faster
When Stuart said speed, he didn't mean the model runs quicker. He meant he stays in the work longer. When the custom app you're building has complex business logic and integrations where one change ripples through five files, being able to stay in a single session without losing context changes how the day feels.
Perhaps it's thinking faster, because it just has more context all the time.
Stuart Cox, CEO — Northbase
It's a fair point. When the whole codebase is already loaded, the model doesn't spend time re-finding things. It just gets on with it.
Stuart's honest about the skepticism too. His first reaction was that it felt "too good to be true." So he tests it. He asks the model to review its own work across entire sections, and it catches real issues - twelve on one occasion. Review, fix, confirm, move on. Trust builds gradually, not all at once.
03 — The bottom line
What this means for your project
If you're looking at commissioning a custom web application - something with real business logic, integrations, and moving parts - the tools that build it just got meaningfully better. Not in a press release way. In a "the person building your app can stay focused on your problem for longer" way.
That's a quieter improvement than most people write about. But it's the kind that shows up in the finished product.
04 — Common questions
Custom web app development
How long does a custom web app take to build?
Typically 3-6 months depending on complexity. AI-assisted development tools let teams stay focused on core logic longer, reducing overhead from context-switching. At Northbase, we scope projects individually because integrations, data migration, and business logic vary significantly.
How much does a custom web application cost in Australia?
Most projects range from $15,000 to $80,000 AUD depending on scope and complexity. Budget reflects real-time integrations, payment processing, multi-user workflows, and reporting dashboards. We assess your systems and business logic to give a fixed estimate.
Is a custom app better than off-the-shelf software?
Depends on your business. Off-the-shelf fits standard problems. Custom wins when your competitive advantage lives in unique workflows, proprietary logic, or integrations that standard platforms don't handle. If you're tying together 4+ different systems and your team has processes that standard software forces you to change, custom is usually cheaper long-term.
What industries does Northbase build custom apps for?
Australian mid-market businesses across professional services, trades, real estate, ecommerce, and manufacturing. The common thread is businesses where off-the-shelf software doesn't fit the way the team actually works.
Can you integrate with our existing systems?
Yes. Most custom projects exist to connect existing tools. We integrate with accounting software, payment processors, CRMs, inventory systems, and custom databases. Integration complexity varies, so we assess your current stack early in the scoping process.
Who is Stuart Cox?
Stuart Cox is CEO of Northbase, a digital agency on the Sunshine Coast with 25+ years in the industry and 1,500+ client projects delivered. He leads custom app development and is hands-on in architecture and builds, not a manager outsourcing the work.