clawdex is a local-first, markdown-first personal contact index CLI written in Go. Contacts are stored as plain markdown files with YAML frontmatter in a private Git repository, making the data diffable, grepable, and portable. The tool provides commands to manage people, notes, avatars, search, and timelines, with import adapters for Apple Contacts (macOS only via a temporary Swift helper), Google Contacts (via the gog CLI), X/Twitter DMs (Birdclaw), Discord DMs (Discrawl), and generic crawlkit-compatible crawlers. It also supports vCard export, Git sync helpers, and a doctor command for repairing damaged frontmatter. The architecture is a single self-contained binary with Kong-based CLI parsing, internal packages for each major domain, and a strong emphasis on security and correctness — the safefile package performs rooted, symlink-aware file I/O with atomic writes, and the markdown package includes robust salvage and repair logic for damaged frontmatter. CI enforces 90%+ test coverage, security scanning (gitleaks, gosec), dead code detection, and reproducible builds via GoReleaser.
Radicale is a production-grade CalDAV and CardDAV server implemented in Python. It provides a self-hosted solution for managing calendars, address books, tasks, and journals via standard WebDAV, CalDAV, and CardDAV protocols. The system supports multi-user, multi-collection setups with pluggable backends for authentication (htpasswd, LDAP, IMAP, OAuth2, PAM, Dovecot, remote_user), storage (multifilesystem with caching), rights management, sharing (token/map-based), and web UI. It includes a built-in HTTP/HTTPS server with WSGI compatibility, a browser-based management interface, and extensive configuration options for security, performance, and integration with reverse proxies. The architecture follows a modular plugin pattern: each major subsystem (auth, storage, rights, web, hook, sharing, group) defines a base class and is loaded dynamically via a plugin loader. The core application dispatches HTTP requests through a WSGI application class that handles authentication, locking, logging, and profiling. The storage layer uses a mixin-based design to separate concerns (cache, sync, history, lock, etc.) and stores collections as filesystem directories with individual item files. The sharing module provides a REST API for managing shares, including VCF-to-ICS birthday conversion and property overlays. Key features include CalDAV filtering and recurrence expansion, sync-token support, free-busy reports, email notifications via hooks, and a JavaScript frontend for collection and sharing management. The codebase is well-tested with both unit tests (Python) and integration tests (Playwright), and includes CI/CD pipelines for multi-architecture Docker images and PyPI publishing. While primarily an application, it contains reusable data processing logic for iCalendar/vCard parsing and transformation.
Mac Messages MCP is a Python application that provides an MCP (Model Context Protocol) server for interacting with macOS Messages. It enables AI assistants like Claude Desktop, Cursor, and others to read, search, and send messages through the native Messages app using standard input/output communication. The application directly accesses the macOS Messages and AddressBook SQLite databases, uses AppleScript for sending messages with automatic SMS/RCS fallback, and provides tools for message retrieval, contact search, fuzzy message search, attachment handling, and permission diagnostics. The architecture follows a clean separation of concerns with the MCP server handling protocol communication, and the messages module containing all core business logic for interacting with macOS systems.
Kurrier is a self-hosted unified communication platform designed to aggregate email, calendars, contacts, and cloud storage into a single workspace. It functions as a multi-tenant SaaS application, supporting various protocols including IMAP/SMTP for email, CalDAV/CardDAV for scheduling and contacts, and WebDAV/S3 for file storage. The system emphasizes data ownership and privacy, allowing users to manage multiple email identities and storage volumes within isolated workspaces. The architecture follows a monorepo structure with a clear separation of concerns. The frontend (`apps/web`) is built on Next.js 16 with React 19, utilizing Server Actions for business logic and a Nitro-based worker (`apps/worker`) for background jobs like IMAP sync and email delivery. Data persistence is handled by PostgreSQL with Drizzle ORM, while Redis manages job queues and caching. The platform integrates with external providers via a strategy pattern, supporting services like Google Workspace, AWS SES, and various SMTP providers. Key components include a robust provider abstraction layer for pluggable email and storage backends, a centralized encryption vault for sensitive credentials, and a standardized Server Action wrapper for consistent error handling. The codebase demonstrates high craftsmanship in its sync logic and multi-tenancy implementation, though it carries some technical debt related to type safety and complex DAV/IMAP state management.