01 · THE APARTMENT
Type the apartment once
- Click a door.
- In the purple rail, type the apartment — 3R.
- Press Enter. The door becomes 3R-01.
The preview under the box shows the exact number Enter will mint — it can't lie.

Type the apartment once. Every click after that stamps the next door.
STEP 03 / 0701 · THE APARTMENT
The preview under the box shows the exact number Enter will mint — it can't lie.

02 · THE WALK
Every click numbers itself — 3R-02, 3R-03, 3R-04… — in your walking order. No dialogs on the pass.
Doors that already have numbers won't renumber by accident — a stray click just opens the door for a fix.
03 · CHANGING YOUR MIND
The × inside the purple box clears the apartment and stops the series; Esc does the same from the keyboard. A door that already has its number never renumbers from a stray click.
Typing 2b after 2B-01 still mints 2B-02.
A series at -09 mints -10, never -9.
An ID you typed yourself is never renamed by an apartment change.
Takes back a number and the apartment it recorded, together.