I built a Norwegian net-worth tracker that adds up my bank, stocks and crypto with live prices
I built Pengeflyt, a browser-only net-worth tracker that gathered bank accounts, savings, stocks, funds, crypto and a student loan into one total with a history chart. Crypto values updated in real time from public price feeds, and stock prices came from Yahoo Finance through a small Cloudflare Worker I set up. I kept it an unofficial concept with made-up demo accounts, not affiliated with or endorsed by any bank, broker or exchange, and it never moved real money: buy, sell and transfer only recorded entries in the browser.
What made it work
- The agent tested the app in a real browser and found and fixed its own bugs.
- It went fast from a vague idea to a working app that was live on the web.
The screens
Try itLive at murtaza1701.github.io.
Open ↗Build your own version
Yours goes up next to @muhus’s as a vibe off, and @muhus is told. Credit for the idea stays with them.
How it was madeThe prompt, tools, what’s left to make it real, links.
What’s left to make it real
Fix the remaining low-severity CSV formula-injection finding. Add recurring transfers, such as a fixed monthly saving. Add fund prices (Yahoo only lists Norwegian funds as unnamed codes). Make it an installable app that works offline. Import bank statements from CSV.
- Made with
- Claude Code, GitHub Pages, Cloudflare Workers
- How
- I described what I wanted to Claude Code (Claude Opus 5.5) and made the decisions along the way; the agent wrote plain HTML, CSS and JavaScript with no framework or build step, hosted on GitHub Pages. It wrote the calculations as tested pure functions first (118 unit tests), then the pages, and clicked through every screen in a real browser on desktop and phone sizes. A code review, an accessibility check, a design critique and a security scan found issues that were fixed, except one low-severity CSV export finding.
- The prompt
- jeg hadde litt annerledes tanke på finance tracker, jeg ville ha mer et felles oversikt over formuen min, altså hvor mye jeg har for eksempel har i banken, hvor mye i fond/aksjer, i binance/firi osv, det beste hadde vært å ha oppdatering i sanntid, så hver gang jeg legger inn mer/ tar ut så holder appen/nettsiden seg oppdatertIn Claude Code, GitHub Pages, Cloudflare WorkersModel Claude Opus 5.5
- Hard parts
- Yahoo Finance blocks direct browser requests, so a tiny Cloudflare Worker proxies the stock quotes. Keeping the layout tidy as features piled up took a full redesign into Overview, Bank, Stocks & funds and Crypto pages.
- Try it
- Open the demoRead the code
Building on it rather than answering it? Post a remix and it links back here.
Share it
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1 comment
@muhusbuilder
How would you keep bank balances up to date without bank APIs or keys? Or would you trust AI to vibe code and implement API keys?
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