Claudius: Open-Source Embeddable AI Chat Widget for Claude

Claudius is an open-source, self-hosted chat widget powered by Claude that can be embedded on any website. The project was created to address the common client request for chatbots without requiring expensive SaaS subscriptions or custom development from scratch.
Key Features
- Floating chat bubble that works on any site (WordPress, Webflow, static HTML, React, etc.)
- Backend runs on Cloudflare Workers (free tier handles significant traffic)
- Customizable system prompt to create business-specific AI assistants
- Dark mode with light/dark/auto options
- Conversation persistence and markdown rendering
- KV-based rate limiting to prevent API cost overruns
- WCAG 2.1 AA accessible and responsive down to 320px
- Fully configurable: colors, title, theme, system prompt
Technical Stack
Frontend: React 18, TypeScript, Tailwind, Vite
Backend: Cloudflare Workers, Hono, Anthropic SDK
Implementation
Embedding requires three files: set window.ClaudiusConfig with your worker URL and preferences, include the CSS, and include the JS.
Cost Structure
The only cost is Anthropic API usage. Cloudflare Workers free tier provides 100k requests/day. For small business sites with few daily chats, costs are minimal.
The project is MIT licensed with no telemetry, tracking, or SaaS middleman. It's the third open-source project from the developer's studio, following a React framework (Aurelius) and WordPress framework (Flavian), both Claude Code-integrated.
📖 Read the full source: r/ClaudeAI
👀 See Also

SkyClaw: Rust-Based Autonomous AI Agent Runtime
SkyClaw is an autonomous AI agent runtime built in Rust with a 7.1 MB binary that idles at 14 MB RAM and starts in under one second. It operates on five engineering principles including autonomy, robustness, and brutal efficiency.

Kreuzberg v4.7.0 adds code intelligence for 248 languages and improved markdown extraction
Kreuzberg v4.7.0, a Rust-core document intelligence library, now supports code extraction for 248 formats via tree-sitter and has significantly improved markdown quality with Structural F1 scores over 80% across 23 formats.

Exploring macOS's sandbox-exec for Secure Application Execution
sandbox-exec is a macOS command-line utility that allows applications to run in a restricted environment. Learn how to utilize it with custom sandbox profiles.

Claude TimeTrack: macOS menu bar app that reads Claude Code JSONL files to auto-track dev time per project
Open-source macOS menu bar app that parses Claude Code session JSONL files and git history to auto-track time per project — no manual timers needed.