Paths/MLOps Engineer/Feature Stores / Defining Features
Write the Feature Transformation
The transformation is where the raw events become the columns a model trains on. Write it once, with a schema, so training and serving agree.
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01Requirements
live checks- File ~/feast/features.py exists○
- The file defines a transformation function○
- The file declares the source schema with typed fields○
02Walkthrough
1 of 5 revealed- 01
Write the transformation
One function, one input frame, one output frame. The function name in a feature definition has to match this name exactly.
echo 'def user_activity_features(df, ts):\n df = df.assign(last_seen=ts)\n return df' > ~/feast/features.py - 4 locked · each failed submit reveals one
03Stuck?
0 of 3 revealedTake a hint without losing the lab — each one points at the thing to look at, not at the answer.
04AI Tutor
guides, never solvesTell me what you're stuck on — I'll nudge, not solve. Which requirement are you looking at?
04Notebook
saved locally in this browserlearner@lab — ubuntu:24.04
Session is disposable
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