WHO MADE THIS
Built by Izzy Hodnett with Claude.
The atlas began as a spreadsheet for one table's campaign — a ward of Sigil kept parcel by parcel, so a session could answer who owns the shop, what it is worth and who is behind the counter. This site is that workbook made walkable.
Izzy Hodnett
I keep the workbook, draw the wards and decide what the district is for. Claude wrote most of the code beside me — the generators, the checks and the pages — which is why the credit on every page names us both.
Nothing here is for sale and nothing here is canon. It is a game aid for a table that wanted its city to hold still between sessions.
Portfolio ↗
Source on GitHub ↗
What the atlas holds
The Lotus Blossom District is the hand-kept part: every parcel on it descends from the workbook, down to the tax bill and the name over the door. Around it the rest of Sigil is generated — every ward, district and neighbourhood drawn to the doorstep, on street geometry taken from real cities and renamed. The generated city is deterministic, so the same address always holds the same person, and any of them can be renamed, re-described or removed without the generator losing them.
277
parcels drawn
50
blocks
18
factions
178
people named
How it was built
The pages are Expo and React Native Web, exported as a static site and served from Cloudflare Workers. A Python build reads the workbook and writes the data the site ships with; the street grids are bounded OpenStreetMap extracts, kept for their geometry and stripped of their real names. Every push runs the linter, the typecheck, the data and atlas invariants and a browser suite that holds each page to WCAG AA — the district is allowed to be fiction, but it is not allowed to contradict itself.
The workbook it all descends from is public, and so is the source.
Credits and notices
Unofficial fan work. Planescape and Sigil are property of Wizards of the Coast. This site is not published, endorsed by or affiliated with Wizards of the Coast, and no challenge to their ownership is intended.
Map geometry is derived from OpenStreetMap. Data © OpenStreetMap contributors, available under the Open Data Commons Open Database License (ODbL) 1.0.
Read the ODbL 1.0 ↗