Phase 1 — Billing Statement Export (near-term) Sztab already has time tracking (SZ-71). The missing piece is a billing rate per user per project, which is a small schema addition. With that in place, Sztab can generate a monthly billing statement: grouped by calendar month, with hours × rate and subtotals - exportable as PDF or CSV. This is the "copy-paste into your invoicing system" path, and it's buildable quickly.

Phase 2 — Native Invoice Entity (medium-term) Sztab generates and stores invoices directly: line items pulled from time entries, a Draft => Sent => Paid status lifecycle, PDF rendering, and a shareable link. This makes Sztab the source of truth for contractor-to-Tigase billing - which is exactly our use case.

Phase 3 — QBO Sync (longer-term) As we discussed separately, a provider-agnostic bookkeeping integration layer (QBO first, extensible to Xero etc.) would push finalized invoices out to the accounting system automatically. No double-entry.

I'd suggest starting with Phase 1 as a near-term addition: it has immediate practical value and the groundwork is already there. Happy to scope it formally if you'd like it on the roadmap.