I Built a Finance App With Zero Backend — Here's What I Learned After 2 Weeks

Two weeks ago, I decided to build a personal finance app. Not because the world needs another budget tracker — there are hundreds. I built it because every single one of them wanted my bank credentials, my email, or $99/year. I'm a developer. I know what happens to data on servers. I've seen breaches. I've read the incident reports. And the idea of sending my salary information to someone's PostgreSQL instance — even encrypted — made me uncomfortable. So I made a decision that shaped everything else: zero backend. Zero server. Zero network requests for financial data. Everything stays in the browser. This is the story of what that decision cost me, what it gave me, and what I'd do differently. The Idea: Plan vs. Reality Here's what annoyed me about budgeting apps: they all track what you spent . Past tense. You open the app, see a number, feel bad, close the app. I wanted something different. I wanted to see my plan next to my reality — in real-time. Not "you spent $400 on food this mo