Alpaca is a US-broker that exposes a free read-only API for historical OHLC data — 1-minute through daily bars going back 7+ years for US stocks, ETFs, options and crypto; ~5 years for crypto specifically. The catch is registration: you create a free Paper-Trading account at alpaca.markets (no SSN required for non-US residents in the paper-tier; the paper tier exists for testing and never touches real money), generate an API key + secret in the dashboard, and paste both into TradeOnyx's Settings → Brokers form with the Paper account flag checked.
The BYOAK ("Bring Your Own API Key") connector (TRA-149) already wires Alpaca up. Once connected, TradeOnyx's chart widget and the Backtest tool prefer Alpaca over Yahoo for any US-stock symbol the user has connected — same query, deeper history.
What you unlock vs. the Yahoo baseline:
| Timeframe | Yahoo limit | Alpaca limit | | --- | --- | --- | | 1-minute bars | 7 days | 7+ years | | 5-minute bars | 60 days | 7+ years | | 1-hour bars | 730 days | 7+ years | | Daily bars | unlimited | unlimited |
For anything Backtest-grade on US stocks under the hourly resolution, Yahoo is structurally not enough. Alpaca is.
Three honest reasons we do NOT recommend Alpaca for live DACH trading — they're also the reasons the data-only use case is actually attractive:
1. No Anlage-KAP integration. As a US-broker, Alpaca issues a 1099, not the EU-broker Anlage-KAP. A live-trading DACH resident has to manually transcribe trades into the German tax form — friction that adds up. For Paper trading: irrelevant. No real trades, no tax form, no friction. 2. W-8BEN paperwork every 3 years. Required for non-US residents trading US instruments. For Paper trading: not triggered. No real-money flow means no withholding, no W-8BEN. 3. USD↔EUR currency drag + 30 % US-withholding on dividends. The W-8BEN reduces dividend withholding to 15 % for DE residents, but you still pay the FX spread on every deposit/withdrawal. For Paper trading: zero. No money moves.
All three pain-points exist only when real money is on the line. The Paper-Trading API serves the same OHLC data without any of them.
When to use Alpaca via TradeOnyx: - You backtest US stock strategies below the daily timeframe (5m, 15m, 1h) and need more than 60 days of history. - You want the chart widget on `/dashboard/charts` to render 1-minute candles for AAPL/TSLA/NVDA going back 2-3 years instead of the last week. - You journal US stock trades from your real broker (IBKR, Tastytrade, Trade Republic with US access) and want the post-mortem chart to show the actual intraday context.
When NOT to use Alpaca via TradeOnyx: - You only trade EU/DACH instruments — your native broker's data (or Yahoo's daily) is enough. - You only trade crypto — Binance/Bybit/Coinbase have richer crypto OHLC than Alpaca anyway. - You only trade forex/CFDs — Alpaca doesn't carry those instruments; OANDA / your CFD broker is the data source.
Set-up in 3 steps (≈ 10 minutes):
1. Create an Alpaca Paper account at https://app.alpaca.markets/signup — pick "Paper Trading". As a DACH resident you can register with name + email + DOB; no SSN required at this tier. 2. Generate an API key in the Alpaca dashboard → API Keys → Generate. You get an API Key ID and an API Secret Key. Copy both — the secret is shown ONCE, you cannot retrieve it later. 3. Connect in TradeOnyx: `/dashboard/settings?tab=brokers` → Add broker → Alpaca → paste both keys, leave the Paper-Account checkbox ON → Save. The connector auto-tests the credentials; you see a green pill when it works.
That's it. From the next chart-load or backtest run, TradeOnyx will route the OHLC query to Alpaca instead of Yahoo for US-stock symbols you query.
Why this is the right move at €0: the alternative is a paid market-data subscription on TradeOnyx's side — Polygon ≈ $80/month, Alpha Vantage ≈ $50/month. We deliberately route that cost to zero by leveraging the user's free Alpaca paper account. The trade-off is one user-side step (the Alpaca registration); the upside is no market-data line-item on the TradeOnyx subscription.
No affiliate disclosure here. We earn nothing if you sign up at Alpaca. The recommendation is editorial — we route to whatever produces the best data per zero EUR/month.