Currency exchanges run on a dozen currencies at once, and most still close their books in spreadsheets. Nexto is a multi-currency back-office where double-entry accounting is the default, not an add-on: every trade, transfer and cash movement posts its own balanced document, with live position and profit per currency. Payment receipts customers send over WhatsApp are read by OCR and become real documents. Multi-branch, per-user permissions, Excel/PDF export, 5 languages. Cloud or self-hosted.