xAI says Grok 4.8 is in reinforcement learning, with a soft rollout planned

1. 8:58 AM
   Rohan Paul@rohanpaul_aiX

   Musk says Grok 5 should beat Claude Opus 5.5 within two or three months

   AIElon Musk calls Opus 5.5 "a masterpiece" but says xAI's Grok 5 should exceed it in two or three months, with continued acceleration afterward. He made the prediction in a reply to a user who said Opus 5.5 was not as good.

   
2. 8:06 AM
   Dongxi NLP@dongxi_nlpX

   xAI rewrites RL and inference stack in C/C++ for Grok 4.8

   AIElon Musk says xAI dumped JAX and SGLang and rewrote its entire RL and inference stack from scratch in C/C++. Pre-training for Grok 4.8 is finished and the model is now in RL, with evals starting to climb. A soft rollout to Bot users is planned for later this week.

3. 5:38 AM
   🚨 AI News | TestingCatalog@testingcatalogX

   xAI's Grok 4.8 enters reinforcement learning ahead of soft rollout

   AIxAI says Grok 4.8 is in reinforcement learning, with evaluation scores starting to climb after pre-training finished. Elon Musk says a soft rollout to some Grok Bot users is planned for later this week, and that the model will differ substantially from Grok 4.7.

   

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