DeepSeek, together with Tsinghua University, released a technical report titled 'DeepSeek Elastic Compute (DSec): Efficient Sandbox Infrastructure for Large-Scale Agent Training,' for the first time publicly disclosing the industrial substrate DSec that supports its training from V3.2 to V4.1. The report's author team exceeds 130 people, with Liang Wenfeng listed last. DSec is DeepSeek's self-developed production-grade elastic compute sandbox platform, an internal dedicated infrastructure that was previously introduced in the DeepSeek-V4 report, whose responsibility is to provide a safe and stable sandbox runtime environment for large-scale training and evaluation of large-model agents.
The report distinguishes the underlying logic of agentic reinforcement learning from that of traditional large-model training: the latter is closer to 'answering questions'—the model is given a prompt or math problem, generates a derivation or answer, and the system computes a reward based on rules and backpropagates; whereas agents oriented toward real software engineering or system operations need to actually operate a computer, retrieving code repositories, configuring dependencies, modifying code, executing tests in a terminal, and continuing to debug based on error messages. This distinction is the starting point for understanding all of DSec's design trade-offs.
The direct constraint this brings is: if, in a single exploration of reinforcement learning, thousands upon thousands of agents are exploring simultaneously, the system must instantly deliver tens of thousands of mutually isolated execution environments that must be stateful and highly coherent. The command an agent executes at step ten must be strictly built upon the files modified, binaries compiled, and processes started in the first nine steps. This is not a problem that can be bypassed with a stateless microservices mindset.