Jevscript

A programming language where judgment is a runtime primitive — you write the program, and the program asks Jev (TypeSafe's System One model) narrow, typed questions as it runs. Jev is not the programmer; it's an operator, like +, but for meaning.

Two names, one project:

• Jevscript — the language. JS-ish surface, three question forms (noul, choice, score), typed answers carrying probability and confidence, policy (thresholds, gates, weights) as ordinary code.
• Hocket — the engine that runs it. Parser, interpreter, and the coalescing machinery: lazy judgments flushed as one request per shared state, data dependencies becoming stage boundaries on their own, and answers memoized on (question identity, state hash). A hocket is one line of music split between voices; Jevscript writes the notes, Hocket keeps the line continuous.

The idea

Everything compositional — control flow, arithmetic, thresholds, retries — is code. Only single semantic judgments go to the model:

ask:
  kind   = choice ["bug","billing","feature","other"]
            by "What is the main request in `ticket.body`?"
  urgent = noul "The message conveys urgency or time-sensitivity"

when urgent.p > 0.6 and ticket.tier == "enterprise":
  page "oncall"

The two judgments above run as one API request. The author thinks in judgments; Hocket thinks in requests — coalescing everything constructed over the same state and splitting only where a question genuinely cannot be built until an earlier one answers. The win scales with state size: ~2.7× on input tokens at a ~230-char state (measured, M0), ~12× on document-dominated workloads (TypeSafe cookbook).

Status

M0 done (2026-09-16). PLAN.md is the working spec — design law, semantics decisions, and the milestone ladder — revised after design review. The spike (spike/m0.mjs) confirmed the answer contract and measured the batching baseline; records in spike/m0-record.json.

Milestone	What
M0	done — spike: contract confirmed, baseline recorded
M1	evaluator: parser + interpreter, lazy judgments, memo from day one
M2	coalescing + cache — the thesis under test
M3	policy stdlib (gates, composites, escalate)
M4	example programs; port the typesafe_test car driver
M5	determinism suite, cost harness

Provenance

• TypeSafe docs — the source of truth for primitives, state, and API contracts.
• ../typesafe_test/ — sibling project; Jev already drives a car there through Noul pedals and a Score steering servo. Its zero-dep proxy pattern (API key stays server-side) is the deployment model here.
• TypeScript throughout, per the house stack.