This is part 2 of our series on how Gylder works. In the previous post, we talked about why a single financial dashboard matters. Now let's look at the first step: connecting your bank.
How open banking works
In 2018, the European Union introduced PSD2 — a regulation that gives you the right to share your banking data with authorised third parties. This means you can grant Gylder read-only access to your account balances and transactions, without sharing your banking password.
Here's how it works in practice:
- You choose your bank from a list of supported institutions
- You're redirected to your bank's own login page
- You log in and approve the connection
- Your bank sends your data to Gylder through a secure API
At no point does Gylder see or store your banking credentials. Your bank handles the authentication directly.
What data we receive
When you connect a bank account, we receive:
- Account balances — Your current and available balance
- Transactions — Your transaction history (income and expenses)
- Account metadata — Account name, IBAN, and currency
We do not receive your login details, card numbers, or the ability to make payments. The connection is strictly read-only.
How syncing works
Once connected, your bank data refreshes automatically. Gylder syncs your balances daily, so your dashboard always reflects your latest financial position.
You can also trigger a manual sync at any time by tapping the refresh button on your dashboard. There's a rate limit to prevent excessive API calls — you'll see a countdown timer if you need to wait.
When a sync completes, your net worth chart updates immediately. If you have alerts enabled, you'll be notified of significant changes.
Which banks are supported?
Gylder supports most European banks through our open banking provider. This includes major institutions across the Netherlands, Germany, Belgium, France, and many other EU countries.
When you start the connection process, you'll see a searchable list of all supported banks. If your bank isn't listed, you can still track your balances using manual entries — which we'll cover in a later post.
Multiple accounts, one view
Most people have more than one bank account — a checking account, a savings account, maybe a joint account. You can connect as many as you like. Each account appears individually in your dashboard, and they all contribute to your total net worth.
If you later disconnect an account, it's retroactively removed from your historical data. This means your net worth chart always reflects the accounts you currently have connected — no orphaned data from old accounts cluttering your view.
Your transactions, organised
Every transaction from your connected bank accounts flows into a unified activity feed. You can filter by type (income or expenses), time period, and amount — making it easy to find specific transactions across all your accounts in one place.
Security
Banking connections use encryption in transit and your financial data is encrypted at rest with a unique key per user. We'll dive deeper into our security architecture in a later post in this series.
Next: Tracking Crypto Across Bitvavo, Kraken, and Coinbase →
