Hopper

Hopper is a pioneering agentic development environment tailored specifically for mainframe and COBOL developers. It acts as a modern Cursor, integrating a real TN3270 terminal with mainframe-aware panels that simplify managing datasets, jobs, members, and spool output. What sets Hopper apart is its AI-driven agent capability, which seamlessly operates across z/OS workflows—inspecting datasets, editing PDS members, generating JCL, submitting jobs, parsing JES outputs, and providing insightful explanations for failures. This combination of traditional mainframe tools with intelligent automation makes mainframe development more accessible, efficient, and less error-prone. Compatible across Windows, Linux, and macOS, Hopper aims to modernize mainframe interaction, reducing the complexity and learning curve traditionally associated with mainframe environments, and empowering developers to work faster and smarter.