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No Jev access yet?

Jev is new, and some keys may not have access yet. You can still take the whole course.

Use the adapter backend

Add one line to .env:

.env
JEV_BACKEND=adapter

Now every ask_jev(...) call is answered by your LLM (MODEL) through TypeSafe's open-source system-one-adapter. It exposes the same system_one() API and returns the same response types, so no notebook code changes.

What works

We ran every notebook with JEV_BACKEND=adapter:

With the adapter
Notebooks 01 and 03-12 run, and their built-in accuracy checks pass
app.py and jobs/email_triage.py run
Notebook 02 (the benchmark) needs real Jev, because it benchmarks Jev itself; it stops with a clear message

What's different

  • Slower. Each decision takes an LLM round-trip (~2-3 s instead of ~0.4 s).
  • More expensive. You pay LLM prices, including output tokens.
  • The race tab says so. In app.py, the "Jev vs LLM race" tells you the "Jev" side is really your LLM.

When you get Jev access, switch back with JEV_BACKEND=typesafe (or delete the line). Nothing else changes.