Thoth

The problem

Every Chilean company that invoices must issue DTE (Electronic Tax Documents) against the SII. The technical integration is dense: CAF, XML signing with digital certificate, status polling, contingency mode. Every LATAM SaaS ends up reimplementing the same, badly.

What Thoth does

Thoth is a headless DTE engine over gRPC. Any product in the CultureTech portfolio (Hestia, Chiron, Plutus, Daedalus) or any third-party SaaS consumes DteService and delegates all tax logic.

Capabilities:

• Issue relevant DTE types (Invoice, Receipt, Credit Note, Waybill).
• CAF (Folio Authorization Certificate) management.
• XML signing with ring (Rust crypto).
• Status polling against SII (Maullin for certification, Palena for prod).
• Contingency mode when SII is down.
• Exponential retries with dead-letter for humans.

Current state

Core implementation complete. Pending:

1. Pre-certification inspector passing all 32 SII criteria.
2. Legal review (test set and documentation).
3. Official SII certification (estimate: 3 months from formal start).

Once certified, unblocks Plutus (billing), Dike (accounting) and Kratos (treasury).

Architecture decisions

• Stateless — does not store DTE; only issues and returns them. Storage is the client’s responsibility. This avoids lock-in and simplifies audit.
• gRPC — the client can be any language. Proto files published in the repo.
• No SDK — latency is low with native gRPC. No need for wrappers that hide the contract.

Stack

Rust · tokio · tonic · sqlx · ring · rustls.