StepFun Open-Sources Step Code v0.1.0 CLI AI Coding Tool

StepFun has open-sourced Step Code v0.1.0, an AI-powered CLI coding tool, under the MIT License. The tool handles the full development loop—from reading and editing code to running tests and shipping—within a single command-line interface, with an emphasis on swift execution, high token efficiency, and long-horizon reliability.

In internal evaluations, Step Code scored 80.9% on Terminal-Bench 2.1 and 73.3% on Multi-Frame, the company's self-developed 150-task long-horizon benchmark. It also supports one-command static site publishing via StepPage.

The source code is now available on GitHub.