Billstack is an ERP and invoicing platform for merchants in Germany and the EU. Connect your Shopify store in one click — no technical setup. Orders import in real time including customer and shipping details, and Billstack creates legally compliant invoices (ZUGFeRD, GoBD) automatically. Your catalog and stock stay in sync across all channels, and tracking numbers are pushed back to Shopify. Also connects eBay, Amazon, Etsy, Kaufland, OTTO and Shopware — one back office for everything.

• Real-time order import via webhooks, incl. addresses and payment status
• Automatic, legally compliant invoices (ZUGFeRD e-invoicing, GoBD)
• Product catalog import and continuous stock sync (Billstack as stock master)
• Tracking numbers pushed back to Shopify automatically
• Multi-channel: eBay, Amazon, Etsy, Kaufland, OTTO, Shopware in one back office