KSeF InvoSync

KSeF InvoSync is a free, open-source browser extension that connects the Polish National e-Invoice System (KSeF) to Google Sheets — automatically. ═══════════════════════════════════════════ ✨ WHAT IT DOES ═══════════════════════════════════════════ ▸ Pulls your invoices (outgoing + incoming) from KSeF every 30 min / 1h / 3h / 6h in the background ▸ Appends them to your own Google Sheet (two tabs: Invoices + Incoming) ▸ Shows a Dashboard tab with live formulas — totals, VAT, balance ▸ Adds 5 charts: gross by date, VAT trend, by buyer, monthly net ▸ Shows recent incoming invoices in a messenger-style feed with unread badges ▸ Click any incoming invoice to view it inline — FA(3) XML parsed on the fly (seller, buyer, line items, totals, due-date banner) ▸ One-click "Add to Calendar" on unpaid invoices — payment due date goes straight to Google Calendar with 3-day + 1-day popup reminders ▸ Download the original FA(3) XML for any invoice ▸ Chrome notifications for new invoices, sync results, errors ═══════════════════════════════════════════ 🔒 SECURITY FIRST ═══════════════════════════════════════════ ▸ Your KSeF token is encrypted with PBKDF2 + AES-256-GCM, protected by YOUR passphrase ▸ No backend server — data goes directly between your browser, KSeF, and Google ▸ No telemetry, no analytics, no tracking ▸ Uses browser-native Web Crypto API (SubtleCrypto) only — no third-party crypto libraries ▸ Minimal permissions: storage, alarms, notifications, identity (for OAuth) ▸ Open source under GPL-3.0 — verify every claim in the code ═══════════════════════════════════════════ ⚡ FEATURES ═══════════════════════════════════════════ ▸ Auto-extract NIP from pasted KSeF token — no manual typing ▸ Connection test button — verify your token works before syncing ▸ Sheet picker — choose an existing spreadsheet or create a new one ▸ Dedup — only NEW invoices are ever appended, no duplicates ▸ KSeF environment switch: Test / Demo / Production ▸ Full Polish + English interface (with manual language override) ▸ Dark/light mode (follows system or manual toggle) ▸ Status badge on the extension icon shows sync health at a glance ▸ "Remember passphrase" option — auto-sync survives browser restart ═══════════════════════════════════════════ 🎯 WHO IT'S FOR ═══════════════════════════════════════════ ▸ Polish SMBs (małe i średnie przedsiębiorstwa) who need KSeF compliance ▸ Accountants managing multiple invoice streams ▸ Freelancers who want their invoices backed up outside the KSeF portal ▸ Anyone who prefers Google Sheets over proprietary accounting software ▸ Developers who want to build on their invoice data (Sheets → custom analysis) ═══════════════════════════════════════════ 📦 HOW IT WORKS ═══════════════════════════════════════════ 1. Install the extension 2. Click the icon → Config tab → paste your KSeF token (NIP auto-detected) → set a passphrase → Set up vault 3. Connect your Google account → authorize Sheets + Drive access 4. Status tab → Sync now → your invoices appear in a new Google Sheet 5. Enable auto-sync → the extension keeps your sheet up-to-date automatically ═══════════════════════════════════════════ ❓ REQUIREMENTS ═══════════════════════════════════════════ ▸ A KSeF account (free, register at ap-test.ksef.mf.gov.pl or ap.ksef.mf.gov.pl) ▸ A KSeF token (generate from the KSeF web app) ▸ A Google account (for Sheets access) ▸ Chrome 120+ (or any Chromium-based browser) ═══════════════════════════════════════════ 🔗 LINKS ═══════════════════════════════════════════ ▸ Source code: https://github.com/k0ss11dev/KSeF-InvoSync ▸ Privacy policy: https://github.com/k0ss11dev/KSeF-InvoSync/blob/main/PRIVACY.md ▸ Issues / feedback: https://github.com/k0ss11dev/KSeF-InvoSync/issues ▸ License: GPL-3.0-or-later