Short answer: For GDPR-compliant EU marketplace audio transcription, choose a speech-to-text API only after its data residency, SOC 2 scope, retention controls, and export behavior pass a provider-portability test in the startup app.
Choose the processing boundary before choosing the speech model. The app transcribes voice reports and classifies them before human review, so model quality still matters, but provider portability is the decision axis: a slightly better transcript is a poor bargain if replacing the processor means rewriting moderation, storage, and review workflows.
That leads to a plain data flow. The app creates an opaque report ID, checks that the selected processing profile is approved for the report's region, sends audio through one internal transcription boundary, validates the normalized result, and passes text to a separate classifier. The human-review system receives the original report ID, transcript, labels, and evidence about which policy profile ran. Vendor-specific request fields stop at the adapter. Raw audio, transcripts, and audit records each get an explicit retention rule instead of inheriting one accidental default.
Keep that boundary boring.
Test it early.
