Introduction

The core design philosophy of DeepSeek Harness (DSH) is “everything is a plugin.” For developers, directly replacing interface styles during local debugging or runtime often requires modifying source code or writing complex CSS. DSH Theme Lab provides a ready-to-use theme collection and development templates, turning style customization from scratch into configurable modules.

What Is This

This is an unofficial modular theme collection and starter pack for the DeepSeek Harness preview (0.1.1-rc.2), authored by Slymaster. It addresses the lack of multi-theme switching and persistent settings in native DSH. By injecting native setting selectors and a semantic token palette, it provides a complete solution that includes four custom themes and the default theme.

Core Features

  • Multi-theme support: Includes four custom themes (Event Horizon, Cyber Sakura, Obsidian Gold, Digital Rain) along with the DeepSeek Harness default theme.
  • Data-driven registry: Creates a single data-driven registry to manage cards, palettes, artwork, and resource routing.
  • Semantic tokens: Each custom theme contains exactly 16 semantic tokens, with both light and dark values.
  • Native persistence: Uses the Harness connection service for native settings persistence, without relying on localStorage.
  • Scoped artwork: Responsive WebP hero artwork, scoped only to [data-phase='hero'].
  • Safe uninstallation: When selecting the default theme or uninstalling, it can revert token overrides and perform a full cleanup.
  • Creator fallback: Provides a lightweight Creator fallback for testing the Event Horizon palette without including artwork or settings.

Installation and Activation

  1. Clone the repository and build it:
git clone https://github.com/Slymaster/dsh-theme-lab.git
cd dsh-theme-lab
corepack enable
pnpm install --frozen-lockfile
pnpm bundle
pnpm link --global
  1. Link the plugin to the Harness configuration directory:
pnpm link --global dsh-theme-lab
  1. Merge the single-line configuration into Harness’s cordis.patch.yml:
- insert:
    - id: dsh-theme-lab-live
      name: dsh-theme-lab

Typical Usage

After starting Harness, go to Settings -> General -> Interface theme. Select one of the following themes from the list:
- DeepSeek original (default)
- Event Horizon
- Cyber Sakura
- Obsidian Gold
- Digital Rain

Use Cases and Notes

This plugin is suitable for developers who need to quickly switch interface styles in a DSH environment or use it as a starting point for developing new themes.
- Dependencies: Requires DeepSeek Harness version 0.1.1-rc.2 and Node.js 22.
- Permissions note: The plugin runs with DSH process permissions. Review the source code and license (MIT) before installing.
- Updates: Check the compatibility notes before upgrading Harness or Node.js versions. If you need to update an installed theme, follow the two-stage process described in the documentation to avoid cache conflicts.
- Residual settings: After uninstallation, saved dsh-theme-lab preferences may remain harmlessly in the Harness Settings document.

Wrap-up

DSH Theme Lab standardizes interface customization and lowers the barrier to theme development. For more details or to report issues, visit the project directory or the GitHub repository.