References · Case Studies

Real projects. Live operations.

No demo screenshots, no mockups. Real-world cases from live operations — real restaurants, real tax firms, real DATEV exports.

Reference 1 · since 2024

TopTuna · office.toptuna.de

B2B fish wholesale ERP · Berlin · hospitality supplier for restaurants

Starting point

Inconsistent delivery platform and bank data caused manual reconciliation and delays in the monthly DATEV handover. No structured transfer to the tax firm.

Solution

GPAA consolidates platform data, runs plausibility checks and produces a review report with open items. Fully digital — no manual sorting.

Result

The tax firm receives DATEV-Buchungsstapel, review log and receipt ZIP. Fewer queries, reliable submission deadline, stable DATEV import.

  • Java Spring Boot + Angular · live since 2024
  • DATEV-Buchungsstapel + review log + receipt ZIP
  • Lieferando, Wolt, Uber Eats — platform settlements processed automatically
  • Hosted on Hetzner · EU hosting · GDPR-compliant

Reference 2 · from 2026

GPAA Accounting Firm SaaS · Pilot phase

B2B SaaS for tax firms with hospitality clients · flat-rate licence

Starting point

Tax firms managing multiple hospitality clients face different intake channels, manual pre-sorting and missing documents — the same problem repeated for every client.

Approach

One firm licence (flat-rate) covers all hospitality clients. Each client gets its own portal. The firm keeps full control over all clients in one dashboard.

Model

TopTuna refers accounting firms as a partner. Firms pay a flat-rate (199–999 EUR/month); restaurants use GPAA as sub-clients free of charge within the firm licence.

  • Pilot phase starts 2026 · first firms in acquisition
  • Tiers: TEST (free, 3 clients) · BASIS (199 EUR/25) · PRO (499 EUR/100) · ENTERPRISE (999 EUR/unlimited)
  • Firm dashboard: all clients, all statuses centralised
  • DATEV export per client · cancel monthly

Learn more about the firm SaaS model →

TopTuna as referral partner

TopTuna is not only a reference customer but also a sales partner: TopTuna refers accounting firms that want to handle their hospitality clients via GPAA. This creates a direct link between fish supplier, restaurant and tax firm — all on one platform.

  • TopTuna knows the restaurants from its own delivery operations
  • Tax firms serving TopTuna restaurants find their way to GPAA naturally
  • Referral model: 50 EUR one-off per referred firm + 5 % of monthly flat-rate

Your project as the next reference?

DTNSoft supports hospitality and DATEV projects from data capture to export. Contact us for a pilot or a demo without real data.