What's actually inside an EU AI Act Annex IV technical file (and what engineers usually miss)

If you're building a high-risk AI system for the EU market, you'll eventually need to produce an Annex IV Technical File. Most engineers have no idea what's in it until someone from legal drops a deadline on their desk. Here's what it actually contains, what you need to build, and where teams consistently fall short. What is the Annex IV Technical File? It's the mandatory documentation package that high-risk AI system providers must compile before placing their system on the EU market. Think of it as the technical dossier a notified body or national authority would review if they came knocking. It's defined in Article 11 of the EU AI Act, with the full list of required contents in Annex IV. Who needs it? Providers of high-risk AI systems under Annex III (employment screening, credit scoring, biometric identification, critical infrastructure, etc.) and systems integrated as safety components of regulated products under Annex I (medical devices, machinery, etc.). Deployers don't need to