DeepSeek open-sources V4.1 Flash 1017, a 763B model that codes from a single wish

On 17 October 2026, DeepSeek released and open-sourced V4.1 Flash 1017 under the MIT license: a 763-billion-parameter MoE with a one-million-token context and self-feedback RL post-training that improves coding and agent use. Existing deepseek-flash API users get it with no code change and no price increase.