System Puzzles

Elevator

Open · version 0.3.0 · updated 6 Oct 2026
The Elevator title screen beside a ten-storey office building with two liftsPlay here
Runs in this page · saves on its own · mouse or touch

Your line

20 levels · Progress is kept in this browser
  1. The First Day1–5
  2. Office Hours6–10
  3. The Growing Tower11–15
  4. The Skyscraper16–20
  1. The First Day1–5Start here
  2. Office Hours6–10
  3. The Growing Tower11–15
  4. The Skyscraper16–20

About this line

You don’t drive the lifts. You write their rules, start the day and watch the building keep them.

A rule is two cards. Each car reads your list from the top whenever it reaches a floor, so the order of the cards is the program.

Someone is waiting hereStop, open the doors
Level 7, two lifts sharing ten floors
Level 7 · A second car
Level 13, an express lift that only stops at the lobby and the top floors
Level 13 · Express
Level 20, four lifts in a twenty-two-floor tower with a car park, at noon
Level 20 · The Skyscraper · four cars, twenty-two floors