How to build a user wallet feature in Bubble

A wallet in Bubble is just a field on the User (for example Balance as a number) plus a safe way to change it using backend workflows. The user never updates their own balance directly in the browser. Instead, you run an API Workflow that receives an amount and safely adds or subtracts it. Each change should also create a Transaction entry so you always have a history.

Core Structure

The simplest working wallet uses a number field on the User: balance. Every time money enters or leaves, you trigger a backend workflow that updates this field. You should also create a Transaction data type containing amount, type (credit or debit), and the user, so you can show statements later.

• Create a field on User called balance (type: number, default 0).
• Create a data type Transaction with fields: user (User), amount (number), type (text), reference (text).
• Create a backend workflow “wallet-adjust”. It accepts inputs: user (User) and amount (number).

Backend Workflow Logic

Inside the backend workflow, safely change the balance using “Make changes to thing → User”. Then log a Transaction entry. This ensures calculations happen on the server, not the user’s device.

// Step 1: Update user balance
Make changes to User (workflow input user):
balance = This User's balance + amount

// Step 2: Log a transaction
Create a new Transaction:
user = workflow input user
amount = amount
type = amount > 0 ? "credit" : "debit"
reference = "Wallet adjustment"

Triggering the Wallet Update

On any page, when a user performs an action (like deposit, refund, payout), call the backend workflow using “Schedule API workflow”. You pass the current user and the amount. Amount can be positive (add) or negative (subtract). This avoids any race conditions from multiple updates happening at once.

• On button click → “Schedule API workflow → wallet-adjust”.
• Set user = Current User.
• Set amount = 10 (or dynamic value).

Privacy Rules

In Privacy settings, only allow the Current User to see their own balance. Never allow users to modify their own balance. Backend workflows bypass privacy rules safely.

• User: When Current User is This User → allow “View balance”.
• Never allow “Modify balance”.

Displaying the Wallet

On the dashboard, just show Current User's balance and a repeating group of Transactions filtered by user = Current User, sorted by Created Date descending.