Recurrent Looped Transformer extends looped architecture across tokens, adding depth per token

omarsar0 · x · 2026-09-14

A new technical report extends the popular looped transformer idea across tokens. Recurrent Looped Transformer (RLT) makes the decoder recurrent over every token, prompt and response included: a causal encoder builds global KV memory, and for each new token the decoder combines the encoder representation, its own previous final hidden state, and a sliding-window cache of recent activations. With a 48-layer decoder, the compute path after t tokens runs through 48t blocks while per-token cost stays fixed. The same state transition serves pretraining, SFT, sampling and RL replay, with no reset at the prompt-response boundary; RL replay rebuilds states under current weights instead of reusing stale rollouts.

Related event: RLT: Recurrent Looped Transformer Goes Open Source With Cross-Token Recursion(6 posts)→

Original post →

More from Models

Models channel →