Architect

Sep 14, 2026 · Artificial Intelligence

DeepSeek V4.1 Flash Architecture: The State Lifecycle Behind 1M Context

This article dissects DeepSeek V4.1 Flash's architecture for 1M-token context, explaining how CED reduces prefill compute, CSA2 shares global KV across layers, hierarchical sparse indexing narrows search, FP4 quantization shrinks storage, SWA uses bounded replay for recovery, and Engram adds a conditional memory path—revealing five cost dimensions of long-context deployment.