Free call
A free 30-minute call with Devin. No purchase required.
How we work
- Steps
- Five
- Access
- Read-only first
- You approve
- Each milestone, What ships
Where the hours go
Good software. The work falls in the gaps between it.
Most established businesses already pay for good software. Zero Sum fixes one of these gaps at a time, inside the tools you already have.
Sound familiar?
Scenes in an owner's words.
Scene 1
An enquiry arrives on Friday afternoon. Nobody answers it until Tuesday.
Scene 2
Bookings live in one app and invoices in another. Someone types them in twice.
Scene 3
Only one person knows how the month-end report gets made.
Scene 4
The automation someone set up last year stopped working. Nobody is sure when.
The five steps
Access checked before any promise.
Step 1: Call
Free, 30 minutes, with Devin. You leave with a suggested first step and its price, or a plain answer that it isn't a fit.
Step 2: Feasibility check
$1,000 at signing. Five hours of read-only work on your own systems, with a live sample. You get a written go or no-go and a fixed quote. If your software blocks access, the work stops here.
Step 3: Build
Before building, you and Devin agree the tests the workflow must pass. Half the fee is due now; the $1,000 counts toward it.
Step 4: Acceptance
The other half is due when the tests pass. If they still fail after 10 business days of fixes, that milestone's fee is refunded. Then 30 days of defect correction.
Step 5: Next
Approve the next milestone on its own, keep it running with monthly support, or stop.
Read-only access comes first. You approve each milestone before it starts.
Business OS is Zero Sum's own operating system, built with the same method. Zero Sum is its first tenant.
Internal work, not a client result. Client work appears here only with the client's written consent.
Method
The method, labelled as what it is.
Read-only first
Zero Sum looks before it touches. Write access comes later, only for a build you approved.
Knowledge capture
How the work really runs gets written down, so it no longer lives in one person's head.
Cited data
Numbers in a report point to where they came from. Nothing is estimated and passed off as measured.
Human approval
AI agents do parts of the build. Devin checks the result before you see it, and you approve what ships.
Fair questions
Asked before every first call.
What access do you need?
Read-only access first, for the feasibility check. Write access only when a build needs it, and only after you approve it. The proposal says what Zero Sum can see.
What if it doesn't work?
There are two exits. If your software blocks access during the check, the work stops there and you get the reason in writing. If the build fails the tests you agreed, Devin has 10 business days to fix it; if it still fails, that milestone's fee is refunded.
Who owns the work?
Every proposal states who owns the work and how you export it, before you sign.
What will it cost to run?
Every proposal estimates the running costs: hosting, model usage and software. They are billed at cost and shown before you sign.
Who is this not for?
If you want to replace all your software at once, or want a fixed price for the whole business before anyone has looked at it, Zero Sum is not the right fit. If your software will not allow outside access, the feasibility check finds that out before any build starts.
Do you work only with certain industries?
No. The work starts from a workflow and the software behind it, not from an industry.
