Shaun Sergay
Founded and led eGuarantee — $150m+ in digital bond issuances.
Across AU/NZ, with adoption among tier-1 institutions. Ex-PwC; postgraduate in commerce and information systems.
Who we are·Aeterna Systems
The house behind the table.
Sitdown is the SME arm of Aeterna — the house behind builds that run inside financial services, property, and regulated industries. A principal sits at every Sit-Down; both sign every sealed brief. The same hands, calibrated to operators.
From single-founder ventures to dual-listed data providers and top-tier law firms — same discipline, calibrated to your stakes.
01The posture
What you get, working with us.
Who
A principal in the room. Both signatures on your brief.
What
Working software in weeks. Not a deck. Not a prototype.
How we talk
Plain. If we don't know, we say so before you have to ask.
What stays private
Your name, your business, and what we're building. Always.
02What we promise
The four things we won't move on.
The same hands that build for financial services and regulated industries. What you get is your own sealed software — yours, on your own surface, traceable to your own words, warranted. Working software, in weeks.
We ship real software, not prototypes.
Working software
Built to be used, not demoed. If we can't ship something real in weeks, we say so before you sign — no demoware in disguise, no slides standing in for a product.
We pressure-test every call before we sign.
Two signatures on every brief
Two of us examine every meaningful call before either of us signs. Cheaper to catch a weak spot on a Tuesday than ship a brittle thing to your team.
We tell you when we don't know.
Straight talk, not spin
If we hit a wall of any kind — technical, build-shape, anything — you hear it from us first. Before the deadline slips, before the invoice. We don't write that a thing is so when it isn't.
90 days on us.
First 90 days, no clock
After Launch, three months where the line stays open. Something breaks, we fix it. No clock running, no extra invoice.
03Leadership
Who you'd be sitting with.
A principal in the room. Both signatures on every sealed brief — applied by hand. Shaun leads the institutional conversation; Alex builds.
Alex Zarov
Career entrepreneur and systems architect.
A background in critical infrastructure. Combines deep technical skill with a builder's instinct for what a business actually needs.
The wider team
A principal sits at every Sit-Down. The roster is deliberately tight. After Launch, Aeterna's wider team holds the continuity — facilitators, delivery, operations. Held in confidence, like our clients.
04Operating principles
How we work, in six lines.
01
Open-ended start.
Story first, never a structured form. The story is the brief.
02
Constraint over enumeration.
What can't it do? Negative space shapes the positive.
03
You use it. We sit with what you find.
The first cut runs in your real week. You tell us what's wrong. We build the feedback in — at our cost — before anyone talks about going live.
04
One promise. Both sign it.
The brief carries a single promise statement — what we'll build, said plainly. Both parties sign that sentence; that's the boundary. Nothing gets moved after.
05
We tell you when we don't know.
If we hit a wall you hear it from us first. We never write that a thing is so when it isn't.
06
90 days on us.
Three months from Launch where the line stays open. Something breaks, we fix it. No clock.
There's a seat at the table.
Or write directly to hello@sitdown.au or call 0475 431 338