---
id: FIN-WP-0005
type: workplan
title: "DATEV accounting adapter operations"
domain: financials
repo: fin-hub
status: active
owner: codex
topic_slug: financials
created: "2026-08-11"
updated: "2026-08-11"
related:
  - FIN-WP-0002
state_hub_workstream_id: "58432770-da19-5b72-a946-cacbe1eb24ca"
---

# FIN-WP-0005 — DATEV accounting adapter operations

## Goal

Operationalize the provider-neutral accounting handoff selected in
`FIN-WP-0002`: DATEV Unternehmen online is the bookkeeping and document
authority, with Qonto as the preferred complementary invoice workflow and
managed DATEV transport where its capabilities are sufficient.

This workplan does not authorize fin-hub to issue invoices, assign legal
invoice numbers, execute payments, or perform bookkeeping.

## Confirm operational capabilities and ownership

```task
id: FIN-WP-0005-T01
status: todo
priority: high
state_hub_task_id: "7cdda85d-cdd6-544c-b873-f27ec7ef448d"
```

With the operator and Steuerbüro, confirm the enabled Qonto plan, DATEV tenant
and services, customer/tax master-data owner, invoice workflow, document
retention policy, correction procedure, and required structured fields.
Record which capabilities use Qonto's managed DATEV services and which require
a direct DATEV integration. Route credentials only after this selection.

## Implement the selected transport

```task
id: FIN-WP-0005-T02
status: wait
priority: high
state_hub_task_id: "c2e0b529-43d5-5c17-af07-8140ae98d4c2"
```

After T01, implement the authorized transport behind the existing adapter
contract. Prefer the managed Qonto-to-DATEV route when it preserves the full
required record; otherwise use the approved DATEV API/export surface. Keep
authentication and network side effects outside pure payload preparation.

## Validate legal and bookkeeping completion

```task
id: FIN-WP-0005-T03
status: wait
priority: high
state_hub_task_id: "c6b3177a-a9a3-5a91-9917-ffca94f77d7a"
```

In a non-production tenant, demonstrate customer and tax completion, legal
invoice numbering and issuance by the authorized external system, document
arrival in DUO, bookkeeping visibility, exception handling, and correction or
cancellation flow. Do not treat transport acceptance as bookkeeping proof.

## Certify upgrades and rollback

```task
id: FIN-WP-0005-T04
status: wait
priority: medium
state_hub_task_id: "0be9e6cf-504f-5c63-a31c-12a9390fc79e"
```

Golden-test and dual-run the selected adapter against the same stable billing
basis IDs. Reconcile counts, amounts, currencies, exceptions, and evidence
references; record provider and adapter versions, cutover approval, monitoring,
and rollback procedure.

## Acceptance

- [ ] The Steuerbüro and operator have accepted the responsibility matrix and
      selected transport.
- [ ] Provider credentials are routed through their proper custodian and are
      absent from Git, artifacts, and logs.
- [ ] A non-production end-to-end transfer is reconciled in DATEV.
- [ ] Issuance, payments, and bookkeeping remain outside fin-hub.
- [ ] Upgrade, breaking-migration, monitoring, and rollback controls are tested.