1:1 mentoring with Big Tech AI engineers
System Design

Data Flywheel

The system loop that turns production traces into eval cases, fixes and training data under a review budget, a consent and minimum-tenant gate, a frozen holdout and a release-gate sequence, with what hosted Claude can and cannot train stated.

Last updated

Production11 min readFirst readThe Eval StackPII Detection

After this section you can

  • Route a production failure to the cheapest fix that works
  • Gate production data for training with consent, scrub, a tenant cap and a frozen holdout
  • Diagnose an inflated offline score as leakage before you retrain
24

Data Flywheel

Turn production failures into fixes you can prove: join each signal to its response, set the review budget, and gate the data before anything trains on it.

Key idea

Feedback is a test only once it is joined to the response that produced it. Each failure becomes an eval case or the cheapest fix; training comes last, and only what beats a frozen holdout ships.

Signals become fixes only through a join, a budget and a gate
ONE LOOP, ONE JOIN KEY 1 Serve and trace trace ID and prompt version, model, docs 2 Join signals by response ID feedback and verdict 3 Triage a fixed weekly budget plus a random slice 4 Pick the lever the cheapest fix that works, tried in order 5 Gate, then ship frozen holdout and a canary Levers, cheapest first eval case, prompt, retrieval or tool, routing training last, and only on open-weights models ship, then serve again

Blue input, purple joined state, amber decisions, green output; teal is the loop. Pans sideways on a phone.

Related

More in System Design

Get full access to all 149 sections with code examples, diagrams, and interactive animations.

Unlock Premium