Kasetto

Kasetto is a declarative environment manager for AI coding agents. It syncs skills, MCP servers, slash commands and instructions from Git repositories into the agents a developer uses, driven by a single YAML file and pinned by a lock file. The vendor describes it as written in Rust and shipped as one static binary for macOS, Linux and Windows. It is built for developers and teams who run several coding agents and want the same tools and prompts available in each. The site lists support for Claude Code, Cursor, Codex and Copilot, plus 18 more agents. Each asset is transformed into the target agent's native format and merged automatically. Content is hashed and compared against the lock file, so only what changed is touched, and the tool supports global or per project configuration with an extends option for composition. Sources can be GitHub, GitLab, Bitbucket or self hosted repositories, public or private. Secrets resolve at sync time from placeholders backed by environment variables, 1Password, HashiCorp Vault, KeePass, AWS, Google and Azure secret managers, pass, gopass or the macOS Keychain, so they are never committed or locked. Output can be JSON with real exit codes for use in CI. Installation is by a shell script from the site, and the project is hosted on GitHub with its own documentation. The site's structured data lists a price of zero, and no paid plans are published.