Rest In Pee

Inspiration

It's 7 pm. You just got on the 1 at 50th Street, and you have about ten minutes before it becomes an emergency. Where do you get off? NYC publishes where its public restrooms are, but not whether one is open at the minute you arrive. At 7 pm the city has 185 public restrooms open; by 8 pm, 57; by midnight, 9.

What it does

Rest In Pee tells a subway rider which stop to get off at and which restroom to walk to — free first, paid (buy the cheapest drink) as backup. The Pee Area map shows where you can roam and still reach an open restroom within 5–20 minutes, every half hour from 7 pm to 12:30 am, and plans an A → B walk with a restroom on the way.

How we built it

• Mistral (mistral-small, structured outputs) reads the rider's message — station, line, direction, time, minutes left — and normalizes 146 free-text opening-hours formats from NYC Open Data into open/close times per day.
• Elasticsearch indexes 1,066 NYC public restrooms and 123 verified 24/7 places (OpenStreetMap) with geo_point fields, and answers one query: geo_distance + status: Operational + open at this minute (range on per-day open/close).
• MTA GTFS gives real ride times stop by stop, so for every stop ahead:

$$T_{\text{total}} = T_{\text{ride}} + 2\ \text{min} + \frac{d_{\text{walk}}}{80\ \text{m/min}} \le T_{\text{budget}}$$

We checked every Manhattan station in both directions (306 cases). A free public restroom within 10 minutes is reachable in 35% of cases at 7 pm, 18% at 10 pm, and 0% at 1 am.

Challenges

Opening hours are free text ("8am-4pm, open later seasonally"). And the data lies: fact-checking our top recommendations removed Dunkin' (many NYC stores have no customer restroom), a Krispy Kreme that isn't 24/7, and ER waiting rooms (patients only).

What we learned

"Open now" is the hard part of any place search, and night is where the city's data runs out. Built at the Elastic × Mistral NYC Hack Night with Claude Code.

Built With

• claude