Cal.diy is a fully open-source, MIT-licensed fork of Cal.com, providing a self-hostable scheduling platform. It is a large monorepo containing a Next.js web application (apps/web) for booking pages, settings, and admin, a NestJS API (apps/api/v2) for platform REST endpoints, and extensive packages for business logic (packages/features), integrations (packages/app-store with 50+ apps), embeddable booking widgets (packages/embeds), and reusable React atoms (packages/platform/atoms). The architecture uses tRPC for client-server communication, Prisma ORM with PostgreSQL, Redis caching, and a custom dependency injection system (ioctopus) alongside NestJS DI. Key patterns include a tasker abstraction for async/sync background jobs (webhooks, emails, calendar sync), a versioned webhook payload builder factory, repository pattern over Prisma, and a consistent app-store integration structure. The platform exposes a public API with OAuth2, webhooks, and embeddable components for third-party developers. The codebase is actively maintained with frequent schema migrations and CI/CD pipelines, but exhibits some technical drift due to dual API surfaces (tRPC vs REST), stub implementations for enterprise features, and generated files that require regeneration.
This is a modern Next.js 16 starter template using the App Router, designed to jumpstart full-stack web applications. It provides a production-ready monolith with authentication via NextAuth (GitHub provider), payment processing through Stripe subscriptions, and a PostgreSQL database layer using Drizzle ORM and Neon serverless. The application includes internationalization (i18n) with next-intl, dark mode theming, custom fonts, and standard SEO features like sitemap and robots.txt. The codebase demonstrates disciplined engineering with TypeScript, Zod environment validation, Biome linting, Husky git hooks, and both unit (Jest) and end-to-end (Playwright) testing. While functionally complete and well-structured, it is fundamentally a starter kit composed of framework boilerplate and standard integrations, without innovative or deeply reusable custom abstractions beyond what is typical for such templates.
Papermark is an open-source document and data room sharing platform (DocSend alternative) built with Next.js, Prisma, and a modern SaaS stack. It provides secure document sharing with granular access controls (password, email verification, domain allow/deny lists, watermarking, screenshot protection), real-time analytics (page views, video playback, click tracking via Tinybird), and enterprise-grade features like virtual data rooms with folder hierarchies, group permissions, AI-powered document indexing and chat, signing agreements (Documenso integration), workflow automation, and Slack integration. The platform is monetized via Stripe subscriptions with tiered plans and includes a comprehensive billing/cancellation flow. The architecture is a full-stack Next.js application with a mix of Pages Router and App Router, using Prisma for PostgreSQL ORM, Redis for caching/rate limiting/job stores, Trigger.dev for background tasks, Tinybird for analytics pipes, and Vercel Blob/AWS S3 for file storage. Authentication supports NextAuth.js with passkeys, SAML SSO (via BoxyHQ Jackson), and OTP verification. The codebase is organized with a clear separation of enterprise features under an `ee/` directory, reusable UI components (shadcn/ui-based), and extensive SWR hooks for client-side data fetching. The repository demonstrates solid engineering practices with well-structured API routes, RBAC enforcement, and a rich set of utilities. However, it shows signs of technical drift: simultaneous use of Pages Router and App Router creates inconsistency, some API endpoints are large and monolithic, and there is duplication in folder management and export-visits logic. The rapid schema evolution (many Prisma migrations) indicates active development but also potential instability. Overall, it is a production-quality application with strong reusability in its UI components, i18n pattern, and utility libraries.
This is a production-ready, multi-tenant SaaS starter kit built with Next.js (Pages Router), NextAuth.js, Prisma ORM (PostgreSQL), and Tailwind CSS. The system provides comprehensive enterprise features: email/password authentication, magic link, OAuth (Google, GitHub), SAML/SSO via BoxyHQ Jackson, directory sync (SCIM), webhooks via Svix, audit logging via Retraced, Stripe billing, API keys, and team-based role management (RBAC). The architecture follows a monolith with API routes under /pages/api, middleware for session validation, and a component-based frontend. Data flows center around team creation and management: users register (or SSO), create or join teams via invitations, then configure team-level SSO, directory sync, webhooks, billing, and API keys. The codebase demonstrates solid engineering practices with Zod validation, reusable UI components, and a clear separation of concerns, but shows signs of feature creep and some legacy patterns (e.g., Pages Router). It is well-suited for developers building a SaaS platform who need a jump-start on authentication, team management, and enterprise integrations.