The KwaiKAT Team at Kuaishou has introduced the KAT-Coder-V2.5. It is a coding model trained to operate inside real, executable repositories rather than emit single-turn code. The served model is available through StreamLake. An open-weight variant, KAT-Coder-V2.5-Dev, was released separately on Hugging Face under Apache-2.0.
AutoBuilder: environments that actually run the intended tests
The research frames a verifiable task as a triplet. It needs a precise task description, an executable repository environment, and a set of validation tests. A patch is correct only if it passes all of them.
Tasks are mined from real pull requests and commits, following the SWE-bench lineage. The merged code change supplies a golden patch and the accompanying test change supplies a test patch. Raw issue text is discarded as a specification. Instead, descriptions are regenerated into three parts: a problem statement grounded in the golden patch, requirements derived from the test patch, and interface constraints inferred from both. A clarity check then drops anything ambiguous, incomplete, underspecified, or internally inconsistent.
AutoBuilder handles the environment side. A build agent analyzes the repository and writes a configuration script that installs dependencies and runs tests from a clean checkout. A verification agent executes that script in an isolated sandbox.
