Introducing DSHX: a build-time toolchain for DeepSeek Harness plugins

DeepSeek Harness (DSH) is a platform that runs plugins, but it doesn't come with a build pipeline by default. Developers who want to create plugins as independent npm packages, complete with their own dependencies, tests, and release schedule, are faced with the task of rebuilding the same scaffolding repeatedly. This includes a bundler configuration, a method to type the API exposed by the plugin, a development loop that reloads client code without restarting the host, and a way to verify the manifest before publishing.

To address this pain point, DSHX has been introduced as a small toolchain. DSHX automates the process of typing authoring, defining the host and client components of a plugin together, so that the contract between them is checked at build time rather than discovered at runtime. It also provides a bounded Vite build, which is pre-configured and enforces the boundaries that DSH expects.

These boundaries include what a Host entry may import, what a Client entry may import, and what has to be excluded from the bundle. Additionally, DSHX offers offline diagnostics through the dshx check command. This tool reads the manifest, entry points, and dependency graph without starting the runtime, allowing CI systems to fail a broken plugin before anyone even installs it.

The tool also includes reproducible templates, with the create-dshx command providing a ready-to-use Host + Client plugin with the necessary build, type, and test configurations already in place.

Despite DSH and Cordis still handling execution, scopes, and lifecycle, DSHX serves as the layer that precedes these components. It focuses on authoring, building, checking, and shipping plugins. The quick start guide for DSHX involves using pnpm to create a new plugin (my-plugin), navigating into the created directory, and running pnpm dev to start the development environment.

Detailed documentation can be found at dshx.io, and the source code is hosted on GitHub at github.com/liyown/dshx. It's important to note that DSHX is currently in an early preview stage, and its APIs are subject to change. Developers working on DSH plugins outside of the official repository are encouraged to provide feedback on the plugin model, as their input is welcome.