Marin 535B-A23B reaches training halfway mark as kernel updates lift MFU to 27%

Percy Liang announced that training for the open Marin 535B-A23B model has crossed the halfway mark of its hero run. The model is being developed by Liang and the Marin Community team on CoreWeave infrastructure, with all run changes and metrics tracked publicly in Weights & Biases.

According to Weights & Biases, the run's heldout loss aligns with projections derived from four smaller runs conducted prior to the main training run. Kernel optimizations have improved MFU from 21% to 27%. Run metrics and change logs are documented in the [Weights & Biases training report](https://forge.coreweave.com/wandb/marin-community/marin_moe/reports/535B-A23B-18T-Token-Hero-Run-Scaling-Ladder--VmlldzoxNzc2MDM5Ng).