JevMade field notes / Video guide

Jev in Java and Spring Boot (It's Not an LLM)

Dan Vega demonstrates how to interact with TypeSafe's Jev decision model using standard HTTP requests. He covers Jev's core primitives (Noul/boolean, choice, score) and shows how to call the REST endpoint using plain Java 25 HttpClient and Spring Boot RestClient with Java records.

Original by Dan VegaGetting startedIntermediate25 min 51 sec Published 2026-09-18Source reviewed 2026-09-26

Before you press play

What you’ll find in the video

Jev focuses on parallel decision evaluation rather than text generation, using three key primitives: boolean/Noul probability, multiple-choice selection, and score rubrics.
Because Jev operates via a single REST endpoint (api.typesafe.ai/v1/system1), developers can call it in plain Java using HttpClient without requiring a dedicated Java SDK.
In Spring Boot, developers can map Jev request and response payloads into clean Java records and execute queries with a configured RestClient.

Worth knowing

Gemini-assisted video/transcript review. Fast response times in the video reflect single sample API calls rather than verified performance benchmarks under enterprise workloads, and vendor pricing and speed claims are not independently verified.

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