Receiver-Conditioned State Reconstruction in Hybrid Recurrent Language Models

Language-model programs can compute several candidate branches before selecting one to continue. Saving a full internal state for each candidate increases storage and transfer costs. The retained state of one completed branch can instead serve as a reference for compact records of the other computed branches. The selected branch can then be restored without retaining their shared starting state. For fixed affine branch maps, the theory identifies missing information and corrections that limit error amplification. In short Gated DeltaNet branches, decay matching represents the recurrent state as a scaled sibling state plus a compact residual. A stored lossless bitwise repair corrects numerical discrepancies to recover the native state exactly. On Qwen3.5-4B, repaired records reproduce native cache bits, fresh logits and 128-token continuations at all 64 evaluated endpoints in the same runtime. Across 48 short endpoints, median paired byte ratios are 29.1% relative to canonical lossless Full and 30.1% relative to direct sibling exclusive OR (XOR).