Hacker News AI · 10/17/2026, 16:37:46
DeepSeek V4.1 Flash Launches with Asymmetric MoE for Low-Cost Agents
DeepSeek released V4.1 Flash, featuring a new Causal Encoder-Decoder (CED) architecture and asymmetric Mixture-of-Experts that activates only 8B/16B parameters from a 552B backbone. With native multimodal support and compressed KV caching reducing memory usage by 75%, it targets coding and long-horizon agent tasks, claiming superior performance and speed over the flagship V4 Pro.
SOURCE COVERAGEFull Original Report
DeepSeek V4.1 Flash 1017 is the October 17, 2026 snapshot of DeepSeek V4.1 Flash, served by DeepSeek under the deepseek-flash API model name. V4.1 Flash is a sparse mixture-of-experts model from DeepSeek, and the first built on the company's Causal Encoder-Decoder (CED) architecture. It activates 8B parameters on input and 16B on output from a 552B-parameter backbone, an asymmetric split that keeps per-token compute low relative to the model's total size. Image understanding is native to the architecture, with visual and text embeddings trained jointly from the start of pre-training rather than added afterward as in the earlier experimental V4 Flash Vision ExpOpens in new tab.
It is suited for coding, terminal, and computer-use agents, along with long-horizon tasks that must run to completion across many steps and long-context analysis. Compressed KV caching cuts cache memory to roughly a quarter of the previous Flash generation, significantly reducing costs on agentic workloads. DeepSeek positions it as the cost-efficient tier of the V4.1 family and reports that it exceeds V4 ProOpens in new tab on performance, speed, and task completion time.