fnnzhrn

https://fnnzhrn.ch, the home of a group of friends interested in finance. One Next.js app holds the public site and the members-only tools:

Path	What	Access
/	Landing page (Swiss German copy)	public
/login	One sign-in for all tools (email and password)	public
/depot	Depot: portfolio tracker for shares and cash	members
/cockpit	Cockpit: market dashboard (depot, markets, news, opportunities)	members
/budget	Finanzen: income, fixed costs and how much of it to invest	members

The Depot used to be a separate repository on depot.fnnzhrn.ch. Its full history is merged into this one, and the old subdomain redirects to /depot.

Getting started

npm install
cp .env.example .env.local   # fill in, see "Sign-in" below
npm run dev                  # http://localhost:3000

Command	Description
npm run dev	Start the dev server
npm run build	Production build
npm start	Serve the production build
npm test	Unit tests (Vitest)
npm run lint	ESLint
npm run typecheck	TypeScript type check

How it works

src/
  proxy.ts                 Sends signed-out visitors of /depot, /budget, /cockpit and /assistant/embed to /login
  app/
    page.tsx, site.css     Landing page (styles scoped to .site)
    login/page.tsx         Sign-in, sign-up and "forgot password"; ?next= is where to go afterwards
    login/reset/page.tsx   Sets a new password from the emailed reset link
    depot/                 Depot dashboard (client component)
    cockpit/route.ts       Serves cockpit.html to signed-in users
    cockpit/cockpit.html   Cockpit page (plain HTML/JS, data from /api/cockpit/*)
    budget/                Finanzen page (loads the budget on the server)
    api/auth/[...all]/     Sign-in with email and password (Better Auth)
    api/portfolio, api/profile          The signed-in user's depots and profile
    api/quotes, history, search, resolve Depot market data (yahoo-finance2)
    api/cockpit/*          Cockpit data (see below)
    api/budget             The signed-in user's financial overview
    assistant/embed        The assistant chat alone, for the Cockpit's iframe (/assistant redirects to /depot)
    api/assistant/chat     Answers a question with the user's own Claude API key, streamed
    api/assistant/key      Connects or removes the key; reports what the assistant has cost
    api/assistant/conversations  The chat history: lists, loads, saves and deletes past conversations
  lib/
    auth.ts, db.ts, session.ts  Server-only Better Auth setup, Neon pool, session helpers
    auth-client.ts         Browser side of sign-in
    cockpit/               Cockpit data sources; screens.ts defines markets and screens, screener.ts runs them on Yahoo
    budget.ts              Financial overview: data model and totals
    budget-store.ts, budget-seeds.ts  Loading and saving it; spreadsheets imported per account
    portfolio.ts, storage.ts, sync.ts, swissquote.ts, yuh.ts, ...  Depot logic
    assistant/             The assistant's tools (tools.ts), pricing and stored keys and usage
  components/              Depot UI; site/ holds the landing and sign-in components
db/schema.sql              Database tables for sign-in, depots, budgets and the assistant

Every tool route checks the session on the server: the proxy only does a fast cookie check and redirects, while /cockpit, all /api/* routes except sign-in, and the depot sync verify the session themselves and answer 401 (or redirect) otherwise. They also require the account to be authorized (see below) and answer 403 (or redirect to /login, which says the account isn't approved yet) otherwise.

Sign-in

Sign-in needs three services, all with free tiers: Neon (Postgres) stores accounts and depots, Better Auth handles sign-in inside the app, and Resend sends the confirmation and password-reset emails.

1. Database. In Vercel, open the project → Storage → connect the Neon database. This sets DATABASE_URL. For a new database, run db/schema.sql in Neon's SQL editor (safe to run again).
2. Email. Add a Resend API key as RESEND_API_KEY. To send from your own address, verify fnnzhrn.ch in Resend and set EMAIL_FROM, e.g. fnnzhrn <login@fnnzhrn.ch>.
3. Auth settings. Set BETTER_AUTH_SECRET to a random value (openssl rand -base64 32) and BETTER_AUTH_URL to https://fnnzhrn.ch.
4. Redeploy, so the variables are built in. The tools only open when DATABASE_URL, BETTER_AUTH_SECRET and RESEND_API_KEY are all set; otherwise /login says sign-in isn't set up.

Members sign in with email and password. A new account confirms its email address with a link before it can sign in. Passwort vergessen emails a reset link that works once and expires after an hour; setting a new password signs out every other session. Members from the email-link days have no password yet and set one through Passwort vergessen; their depots and budgets stay with their account. Sessions last a year and renew while the tools are used.

Who gets in. Anyone can create an account, but only accounts marked authorized in the database can use the tools. Mark members in Neon's SQL editor:

update "user" set "authorized" = true where "email" in ('a@example.ch', 'b@example.ch');

Setting it back to false locks the account out on its next request. The column comes from db/schema.sql; on an existing database, run the file again before deploying, then mark the existing members, or they're locked out too.

Depot

Features

• Several depots: keep each broker account (or any other split) as its own depot, with its own transactions, cash accounts, base currency and targets. Switch, add, rename and delete depots from the menu under the title. Export and Import work on the depot shown. All depots adds them up into one view with its own base currency and rebalance targets; transactions and cash are edited in their own depot, and changing a position's asset class there changes it in every depot.
• Record buy, sell and dividend transactions, with fees and withholding tax, and custody fees (Depotgebühren) charged for the account. Custody fees count against total return and show in the fees card; Swissquote imports bring them in too. Symbol search runs against Yahoo Finance, so SIX tickers like NESN.SW and NOVN.SW work, as do US, LSE and XETRA ones.
• Holdings show average cost, the current price, today's change, market value, unrealized P/L and portfolio weight.
• Import from your bank: Swissquote transaction exports and Yuh activity exports (CSV) become transactions and dividends, with tickers checked against Yahoo Finance. A report after each import lists anything that didn't come through. Yuh exports have no balances, so add Yuh cash by hand.
• Cash accounts track your liquidity: add each bank or broker account with its currency and current balance, and edit the balance when it changes. Balances are converted to the base currency and added to your net worth. Importing a Swissquote CSV fills in the account's latest cash balance per currency.
• Summary cards show net worth (shares plus cash), today's change, unrealized P/L, and total return (unrealized + realized + dividends).
• The performance chart plots daily market value against net invested capital, with 1M / 3M / YTD / 1Y / All ranges. The period return excludes deposits and uses the simple Dietz method.
• Multi-currency: pick CHF, EUR, USD or GBP as the base currency. Positions are converted at current FX rates, and history at historical FX rates. LSE prices quoted in pence (GBp) are normalised to GBP.
• Sync across devices: your depots are saved to your account in a Neon Postgres database and load on every device you sign in on. The browser keeps a local copy, so the app opens instantly and edits made offline upload later. Use Export / Import to back them up as JSON.

How sync behaves:

• The first time you sign in on a browser, anything left there from before sign-in was required (or unsaved when you signed out) is merged into your account (matched by depot, transaction and cash account id).
• All depots sync. Which depot is shown is remembered per device.
• Every change uploads right away. When you come back to the tab, it pulls the latest version, so edits from your phone show up on your computer.
• If both devices change the portfolio while one is offline, the last one to upload wins.
• Signing out removes the portfolio from that browser. It stays in your account. Sessions last a year and renew while you use the app.

Notes and limitations

• Cost basis uses the average-cost method. Realized P/L, dividends and cost basis are converted to the base currency at current FX rates. Only the performance chart uses historical FX.
• Cash is tracked as current balances, not as a history of deposits and withdrawals, so the performance chart and returns cover shares only.
• Enter amounts in the share's trading currency, e.g. USD for AAPL and GBP (not pence) for VOD.L.
• Yahoo Finance is an unofficial data source. Data may be delayed, and delisted symbols lose their history.

Cockpit

A tile dashboard that goes from market overview to news to opportunities to buy ideas. Its data comes from free, keyless sources, cached on the server:

Tile	Endpoint	Source
Mein Depot	/api/cockpit/depot	Your depots from the tracker (same calculation as /depot), Yahoo prices
Märkte, Makro-Markt, Beobachtungsliste	/api/cockpit/quotes	Yahoo Finance chart API
Tagesgewinner / -verlierer	/api/cockpit/movers	Yahoo stock screener, per market
Value-Chancen	/api/cockpit/value	Yahoo stock screener (KGV, Gewinnwachstum, Verschuldung)
Schnäppchen-Radar	/api/cockpit/radar	Yahoo stock screener + charts, per market
News zu meinen Aktien, Übernahmen & Gerüchte	/api/cockpit/news	Google News RSS, keyword-tagged
Nächste Quartalszahlen	/api/cockpit/earnings	Nasdaq earnings calendar
Marktstimmung	/api/cockpit/sentiment	CNN Fear & Greed (incl. put/call, VIX)
Buffett-Radar	/api/cockpit/investors	SEC EDGAR 13F filings

"Mein Depot" shows the signed-in user's depots from the tracker, all added up or one at a time, using the tracker's own holdings calculation. Year to date compares today's holdings with those on 1 January, net of this year's buys and sells. The watchlist is stored in the browser's localStorage (export/import as JSON in the editor). None of these sources has an official API contract, so a tile can break if a provider changes its format.

Gainers/losers, the Schnäppchen-Radar and Value-Chancen each come per market: USA, Schweiz, Deutschland, Europa, UK and Japan, chosen with chips on the tile and remembered per device. The lists come from Yahoo's stock screener, called with the crumb and cookies that yahoo-finance2 already holds for the depot's quotes (src/lib/cockpit/screener.ts); the markets, their liquidity floors and the screens are defined in src/lib/cockpit/screens.ts. Secondary listings are kept out by a volume floor and the market's currency. Routes that fan out to many upstream requests set maxDuration, so Vercel gives them a minute.

Finanzen

A financial overview per account: Einnahmen (net income), Fixkosten (costs that are certain each month or year) and Investieren (what goes into the 3rd pillar, shares and so on). Each entry is paid per month, per year, or per month 13× (a salary with a 13th month's pay). The top cards and the split bar show income, fixed costs, investments and what is left, per month or per year, with the fixed-cost share and the savings rate. Monthly figures leave out the 13th month's pay; yearly ones include it and spread yearly costs over twelve months. Changes save to the budgets table as you type.

The budgets table is created on first use. To bring in an existing overview, add it to src/lib/budget-seeds.ts under the account's email: the account starts with it the first time it opens Finanzen, and from then on only what's saved counts.

Assistent

A chat with Claude about the signed-in member's own data, in the corner of every tool (and of the start page for members): a button opens it as a small window, which can be made full screen; on phones it always takes the whole screen. It stays open, in the same conversation, when moving between the tools. The Cockpit isn't React, so it shows the chat in an iframe (/assistant/embed) that the chat sizes itself. Claude reads it through tools (src/lib/assistant/tools.ts) that call the same code as the tools: the depots with current prices (as in the Cockpit's "Mein Depot"), every transaction and cash account, the Finanzen overview with its months and snapshots, and the Cockpit's sources (quotes, news, gainers and losers, Value-Chancen, Schnäppchen-Radar, earnings, sentiment, 13F changes). It only ever sees the data of the member asking.

Each member uses their own Claude API key, so everyone pays for their own questions directly at Anthropic and there's nothing to set up on the server. The chat's settings (the slider icon) walk through it: create an account in the Claude Console, buy credits under Billing (optionally with auto reload), optionally set a monthly spend limit under Limits, create a key under API Keys and paste it in. The key is checked with Anthropic, then stored AES-encrypted with a key derived from BETTER_AUTH_SECRET (changing the secret means reconnecting keys). Entfernen deletes it.

Spend. Every answer records its token counts, estimated cost (Anthropic's list prices, in src/lib/assistant/pricing.ts; update them when prices change) and the key that paid for it (its last four characters, key_hint) in assistant_usage. The chat shows the cost per answer and fnnzhrn's spend today, this month and in total (UTC, like Anthropic's billing), with a breakdown per key. A member's other apps and keys spend from the same Anthropic account, so they can also connect an Admin API key (sk-ant-admin…, assistant_admin_keys, encrypted like the API key): the chat then reads the whole account's month-to-date spend, as training-coach does (src/lib/assistant/account.ts). Past days come from the Cost Report, today from the Usage Report's hourly tokens, cached for a minute. Admin keys only exist in Console organizations. Anthropic doesn't let an API key read the Console's monthly spend limit, so the member copies it in (assistant_spend_limits). The bar under the chat's header shows this month's spend against it (amber from 80 %, red once reached). It's only shown, not enforced; the Console's limit is what stops requests.

Model. Each member picks the model for their answers, saved with their key: Haiku 5.5 (the default, by far the cheapest), Sonnet 5.5 (about 20× Haiku, better at calculations across depots) or Opus 5.5 (about twice Sonnet, for the hardest questions). Answers stream at medium effort. On Sonnet and Opus a refused request falls back to another model on Anthropic's side (fallbacks: "default"); Haiku has no such fallback, so the answer says it was declined.

History. Every conversation is saved in assistant_conversations after each answer (the last 100 per member) and listed under the clock icon, or beside the chat in full screen, to pick up again or delete. The tables are created on first use.

Deploying

The Vercel project for fnnzhrn.ch builds this repo as a Next.js app (vercel.json sets the framework).

Moving over from the separate Depot project

1. In the fnnzhrn Vercel project, add the environment variables from the old portfolio-tracker project: DATABASE_URL (or connect the same Neon database under Storage), BETTER_AUTH_SECRET, RESEND_API_KEY, EMAIL_FROM, and set BETTER_AUTH_URL=https://fnnzhrn.ch. Use the same database, so accounts and depots carry over.
2. Deploy this repo. Check that /login sends an email and /depot shows your depots.
3. Move the domain: remove depot.fnnzhrn.ch from the old project and add it to the fnnzhrn project (Settings → Domains). The app redirects it to https://fnnzhrn.ch/depot. The DNS record stays as it is.
4. Delete the old Vercel project and the portfolio-tracker GitHub repository. Everything, including its history, is in this repository.

What users notice: they sign in once more on fnnzhrn.ch, since browsers keep cookies and local data per domain. Their depots come back from the database. Edits made on depot.fnnzhrn.ch that never reached the server (made offline) stay behind in that browser, so open the old site once while it's still up and let it sync before moving the domain.