JetBrains / Mellum2-12B-A2.5B-Instruct-SFT

[!Note] Research artifact: the SFT-only intermediate checkpoint of the Instruct training pipeline. Use it to study or build on the SFT stage in isolation, run post-training experiments (preference tuning, RLVR, etc.), or compare against the final RL-tuned variant. For product…