Vercel Data: TypeSafe AI's Jev Becomes Fastest-Adopted Model, Used by 35% of Paid Teams in Two Weeks

According to TechCrunch, new data from Vercel’s AI gateway shows that Jev, a “decision model” developed by TypeSafe AI, has become the fastest-adopted AI model on the platform. Within two weeks of its limited release on September 15, Jev was being used by 35% of Vercel’s paid teams, with nearly double the reach of the second most popular model, Sonnet 5.5.

Unlike general-purpose large language models, Jev is designed as a lightweight tool for choosing between predetermined outputs. This architecture allows it to run cheaper and faster than alternatives like Sonnet when classifying large quantities of data. Vercel itself was an early adopter, using Jev to replace GPT-6 Luna for classifying harmful commands. The trend has already inspired competing offerings from OpenAI and Amazon.

The report also highlights continuing momentum for open-source models, which now account for more than 70% of the tokens processed through Vercel’s gateway and nearly 25% of total spend. While spending on frontier labs has grown tenfold, their share of overall spend is decreasing, suggesting that frontier models and open-source alternatives may be complementary rather than competitive. Note that these figures reflect only usage via Vercel’s unified API service and may undercount direct API calls to major labs like OpenAI or Anthropic.