TypeSafe calls Jev a System One model, after Kahneman's
Framed Jev as a System One model for the small in-software judgments that were previously answered by large language models.
The original post
TypeSafe calls Jev a System One model, after Kahneman's fast thinking. Most decisions inside software are System 1 judgments. Which bucket is this. Is this urgent. Approve or flag. We have been renting System 2, a trillion-parameter essay writer, to answer questions a bouncer
Engagement when collected
Numbers are a snapshot taken from X when the case was added to the library (schema v1, collected 2026-09-19); they will not match today.
Where this case fits
Filed under coding & developer tools. In the pattern Jev is built for, the model answers a bounded question per step — and ordinary code acts on the answer, because the answer is already a value rather than a paragraph. Other posts in the same family are on the coding & developer tools page.
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Last updated: 2026-09-22 · sources & corrections · every card links to its author's original post