The afternoon sessions of Day 2 brought compelling demos, forward-looking ideas about AI’s role in policy infrastructure, and the launch of the OpenFisca Association’s first working groups. Here’s our recap.
Afternoon demo sessions
New Caledonia: a simulation that prevented a social crisis
Maxime Bollengier told a compelling story. In May 2024, riots hit New Caledonia. By 2025, company closures had reduced government revenue while surging need increased demand for support. The system was imperfect but not broken — yet the only options on the table were to give less to everyone, or exclude some people entirely.
Enter OpenFisca. Maxime brought the tool directly into policy discussions — no slides, just a basic user interface. They had answers in seconds. The shock: the savings from either option were tiny. The government was about to implement reforms that would hurt people with almost no fiscal impact.
The government made a different choice: employers were asked to contribute more. Housing fund contributions were doubled — from 15% to 30% — for three weeks.
Maxime emphasised that OpenFisca is not just a technical tool — it serves as a bridge between policymakers and citizens.
Trust was built incrementally: first by matching OpenFisca’s numbers to the existing tool to 99% accuracy. Once policymakers saw the numbers matched, they trusted the new tool.
Air Force Cadets eligibility tool
Rob West from the Department of Defence demonstrated a tool built to handle eligibility enquiries coming through the Air Force Cadets’ website. The tool helps users identify whether they’re eligible to join. It was part of the GovCMS Rules as Code sandpit program. Rob is keen to get the tool into production and envisages integrating the tool with the online application process — including proactive emails to eligible applicants.
Scaling rules intelligence: making AI work for Rules as Code
Possum Hodgkin (speaking in a personal capacity) delivered one of the most forward-looking talks of the day, drawing on AI governance experience from Google and Stanford.
Possum argued that every Rules as Code project so far is bounded and small in scope. The real challenge is the unmaintainable future of scoped rules — 30 different definitions of the same concept across 1,000 federal agencies, states, and territories.
The solution Possum proposed is a shared ontological layer. Humans are fundamentally the same — age, income, residence, dependents, citizenship. These are properties of a human, not of any particular Act. Frontline workers already have this human taxonomy in their heads. The task is to build an ontological blueprint that separates the application layer from the legislative corpus, using existing frameworks like W3C, tax treaty networks, and global visa systems as a starting point.
On AI’s role, Possum was clear: not as judge, but as librarian. AI should scan the legislative corpus to document concepts, locate the friction points where Acts diverge, and prioritise the conflicts worth tackling — describing rather than prescribing.
Working groups
The afternoon closed with the launch of the OpenFisca Association’s first working groups — a new format for international collaboration. Three groups kicked off:
- AI: Which use cases are relevant for Rules as Code? What safeguards are needed? What policy for AI-assisted contributions?
- Benefits assessment tools: How to raise public awareness and deliver simulators to users? How to do community organising to update the rules?
- Mutualisation of tooling: How can we avoid duplicate effort? Which systems already exist and should be invested in?
Unfortunately, the Assemblic contingent missed the working groups, as we dashed to the airport and back to Melbourne.
That’s a wrap
The 2026 OpenFisca Conference left us energised and clear-eyed about both the opportunity and the work ahead. Rules as Code is no longer a niche experiment — it’s in production in French Polynesia, it prevented a social crisis in New Caledonia, it’s navigating benefits for citizens in Japan, and it’s being adopted at whole-of-government scale right here in Australia.
At Assemblic, we’re proud to be part of this community — and more committed than ever to building the tools that help Rules as Code deliver on its remarkable promise.