InfillOS
InfillOS is a feasibility engine for small residential infill developers. It checks every parcel in a market against zoning, fits buildings to each lot, runs the pro forma and ranks the results, so you can spend your time on the deals that pencil.
- Status
- Invite-only, live in Durham, NC
- Traction
- 132,562 Durham parcels evaluated. BRM Collective is the founding customer and first investor.
The problem
A single feasibility check, covering zoning, setbacks, a building layout and a pro forma, can take days. So developers evaluate the few lots they happen to hear about, and most viable land is never looked at.
Who it's for: Independent and small-team residential developers who build infill housing and want to see opportunities before the rest of the market does.
What InfillOS does
- Parcel intelligence
- Search every parcel in a target zone with zoning and site constraints already resolved.
- Building envelope fitting
- Layouts are fitted to each lot automatically, including irregular shapes, and shown on an interactive map.
- Instant pro formas
- Each candidate gets a financial feasibility analysis and a score, so the best deals rise to the top.
- Works from your AI assistant
- Search, evaluate and map through MCP tools in Claude or other assistants, or use the web dashboard.
Decisions that shaped it
The product calls behind InfillOS, and why we made them.
AI-native, not another dashboard
Developers already ask AI assistants questions all day, so InfillOS exposes its workflows as MCP tools rather than asking them to learn a new app.
A solver for real-world lots
Infill lots are rarely rectangles. A hybrid genetic-algorithm and simulated-annealing solver packs units onto irregular parcels where simple templates fail.
A partner with skin in the game
Our founding developer partner participates in the profits of deals InfillOS surfaces, which keeps the product focused on deals that actually close.
Built with Python, FastAPI, FastMCP, PostGIS, Shapely, Node.js, Leaflet, Claude API.
InfillOS questions
- What does InfillOS do?
InfillOS scans every parcel in a market, resolves the zoning that applies, fits building layouts to each lot, runs a pro forma and ranks the results by viability. You see the deals worth chasing in minutes instead of days.
- Which markets does InfillOS cover?
InfillOS is live in Durham, North Carolina, covering 132,562 parcels. New markets are added with partner developers.
Ask about your market- Why is InfillOS invite-only?
We're onboarding developers one at a time so each new market is set up with a partner who knows it. Request an invite and tell us where you build.
Request an invite- How does the founding partner model work?
Our founding developer partner, BRM Collective, uses InfillOS on a profit-participation basis and is also an investor. We're open to similar partnerships in new markets.
Build in a market InfillOS doesn't cover yet?
We add markets with developer partners who know them. Tell us where you build.