The MAD Podcast: How AI Gets Built — with Matt Turck

Jev: The AI That Makes Decisions, Not Text - and Why It Changes Everything (Diogo Almeida)

The MAD Podcast: How AI Gets Built — with Matt Turck

Show Notes

What is Jev? TypeSafe’s Jev is a new kind of AI model, a “decision model,” that doesn’t write text. It makes fast, cheap, calibrated decisions inside software, and it has taken the AI world by storm: within weeks of launch it became the most copied model in AI, with OpenAI, Cloudflare, Amazon and Databricks all shipping their own versions, and TypeSafe just raised an $870 million Series A at a $7.5 billion valuation. In this episode, Jev’s creator Diogo Almeida, co-inventor of RLHF at OpenAI and now CEO of TypeSafe, explains Jev in plain English: what a “System One” or decision model actually is, why ChatGPT-style language models can’t be trusted inside software (“95% Einstein, 5% Mr. Bean”), how RLHF and RLVR created the problem, what RLCD (reinforcement learning for calibrated decisions) does differently, where the training data comes from, which models Jev is built on, why “just a classifier” is a compliment, and why he calls pre-training “a giant dumpster fire of wasting resources.”

We also cover the copycats and why he thinks they missed the hard part, why benchmarks are useless, whether Jev will go open source, the Jevons paradox business model behind the name, why he doesn’t believe AI is on the path to recursive self-improvement, and why he thinks the AI winter he feared has been averted.

(00:00) Cold open & Intro: “95% Einstein, 5% Mr. Bean” (01:09) Jev’s breakout launch: why intelligence per dollar matters (03:25) Why TypeSafe built in stealth for two years (05:50) “We could have had AGI last year” (06:48) Why the product carries the marketing (09:33) What is Jev? Machine-native AI, built for software (10:53) System One vs. System Two: the limits of reasoning (12:26) From simple decisions to composable AI (15:21) Automating email: giant prompts vs. smart if-statements (20:03) Probabilities, thresholds, and developer control (23:43) Why Jev is faster and cheaper than chat models (25:39) “Classification is AI-complete” (27:16) RLHF: how OpenAI trained models to please humans (31:28) Sycophancy, refusals, and the hidden costs of RLHF (34:22) RLVR: why benchmark gains don’t mean reliable automation (37:51) RLCD: optimizing for machine-native intelligence (39:54) Why TypeSafe builds its training data in-house (41:49) The Bitterest Lesson: define the task before scaling (44:39) Building Jev from open-weight models (45:56) Is Jev just a classifier? Why that’s a compliment (48:35) “Build prod, not God” (50:11) Embedding AI in software, beyond coding assistants (53:05) Jev’s copycats: matching the interface vs. the intelligence (55:33) Why benchmarks mislead the users they should help (58:37) Open weights vs. APIs: how TypeSafe weighs the tradeoff (1:00:04) Jevons paradox: a new market for machine intelligence (1:02:50) Why Diogo is skeptical of recursive self-improvement (1:04:47) Can practical automation avert an AI winter?

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