MAADU
Live
MAADU answers one question for a homeowner in seconds: could your backyard be an income property? You pick a town, type your address, and the tool fetches the live parcel boundary, building footprint, zoning district, wetlands, and FEMA flood data straight from municipal and statewide GIS servers, then draws your lot, your house, and the largest ADU (accessory dwelling unit) that fits within the real setbacks — to scale and draggable. Beverly runs on the City of Beverly's ArcGIS layers; Peabody runs on MassGIS statewide layers with setbacks hard-coded from the Peabody zoning ordinance. Because MassGIS is statewide, the same engine extends to any MA town by adding its verified setback table. Built as a single static page — no framework, no build step — with one Vercel serverless function for lead and search capture. Live at maadu.homes, framed as "Beverly first, expanding across the North Shore."
Solo · static page + one serverless function · live GIS pipeline
The Problem
Massachusetts legalized ADUs by right in 2025, but a homeowner has no easy way to know if their specific lot can actually fit one. The answer depends on parcel size, the existing building footprint, the zoning district's setbacks, wetlands, and flood zones — data that lives across separate municipal and state GIS systems. MAADU pulls all of it for a single address and draws the answer to scale in seconds, instead of a paid survey or a call to the building department.
Tech Stack
Architecture
Single static index.html — inline CSS + JS, no framework and no build step, so the page loads instantly and deploys as plain files.
Beverly backend hits the City of Beverly's ArcGIS Online feature services (parcels, roofprints, zoning, wetlands, septic, FEMA flood) directly from the browser, all CORS-enabled.
Peabody backend uses MassGIS statewide layers (parcels with zoning + lot size, building structures, MassDEP wetlands, FEMA NFHL) with setbacks hard-coded from the Peabody zoning ordinance §7.2.
A robust address resolver normalizes input (suffix-agnostic, unit-stripping) so any local address format resolves to the right parcel.
Lots are drawn square to the road using MassDOT road centerlines, then the largest compliant ADU rectangle is solved and rendered draggable/resizable to scale.
One Vercel serverless function captures lead and search events (Slack webhooks + Resend email); deployed on Vercel, custom domain maadu.homes.
Key Features
Screenshots
Screenshots coming soon