Guide

Installation

Zerb arrives as a single zip file with everything it needs — no internet required. Extract it to a folder and double-click start_zerb.bat: a small server window opens and minimises itself — leave it running. Then open http://localhost:8765 in your browser. If an “Install” button appears in the address bar, click it — Zerb runs in its own window like a regular desktop app.

First launch

Two steps, both in Settings: pick your currency before adding products, then set yourself a PIN. Until a PIN is set the program asks for no sign-in; from then on everyone taps their name and enters a 4-digit PIN.

Daily sales

No sale happens while the till is closed — the day starts with “Open Cash Session”: you enter the float in the drawer and the program opens the shift. A sale is three moves: scan the barcode (or search by name), pick the payment — Cash, Card, Credit or a split — and press “Charge”. For cash, the change is calculated for you.

Credit sales

A credit sale goes on the customer’s account. The Customers page shows each balance, how many days old the debt is, and the full ledger; a payment is recorded in two taps. A ready-made WhatsApp message lets you remind politely — you send it yourself, the program never messages anyone on its own.

Closing the day

In the evening you count the drawer and record it with “Close Session”. The program computes the expected amount itself and shows the difference: over, short or balanced. The Z-report shows cash, card and credit sales separately.

When the internet drops

Zerb runs on the shop’s own computer, so selling does not stop: cash and card sales continue offline and send themselves when the connection returns. Only credit sales need the internet — and the program says so on screen.

Where your data lives

Every record stays on the shop’s own computer — nothing goes to a cloud. The program takes an automatic backup once a day; since that copy lives on the same machine, exporting a file once a month to a USB stick or your own e-mail is your job. On a new computer the backup is restored from the import page.