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TECH_STACK.md

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+# Technology Stack
+
+This document outlines the technological stack and computer languages used in the BentoPDF project.
+
+## Core Languages
+
+### TypeScript
+- **Version**: ~5.9.3
+- **Usage**: Primary development language for all frontend code
+- **Configuration**: `tsconfig.json`, ES2022 target
+
+### JavaScript
+- **Type**: ES Module (ESM)
+- **Usage**: Build scripts, workers, and configuration files
+- **Files**: `.mjs` and `.js` files
+
+### HTML
+- **Usage**: Page templates and markup
+- **Features**: Handlebars templating for dynamic content
+
+### CSS
+- **Usage**: Styling
+- **Framework**: TailwindCSS v4.1.14
+
+## Build Tools & Bundlers
+
+### Vite
+- **Version**: ^7.1.11
+- **Usage**: Primary build tool and dev server
+- **Plugins**:
+  - `@vitejs/plugin-basic-ssl` - SSL support
+  - `vite-plugin-compression` - Gzip and Brotli compression
+  - `vite-plugin-handlebars` - Template processing
+  - `vite-plugin-node-polyfills` - Node.js polyfills for browser
+  - `vite-plugin-static-copy` - Static asset copying
+
+### Node.js
+- **Version**: 20 (Alpine Linux in Docker)
+- **Package Manager**: npm
+- **Configuration**: `package.json`
+
+## Frontend Frameworks & Libraries
+
+### PDF Libraries
+- **pdf-lib** (^1.17.1) - PDF creation and manipulation
+- **pdfjs-dist** (^5.4.296) - PDF rendering and viewing
+- **pdfkit** (^0.17.2) - PDF generation
+- **jspdf** (^4.0.0) - Client-side PDF generation
+- **jspdf-autotable** (^5.0.2) - Table generation in PDFs
+- **@neslinesli93/qpdf-wasm** (^0.3.0) - QPDF WebAssembly
+
+### Document Conversion
+- **@matbee/libreoffice-converter** (^2.3.1) - Office document conversion
+- **@kenjiuno/msgreader** (^1.27.1-alpha.1) - Email file reading
+- **xlsx** - Excel file processing
+- **papaparse** (^5.5.3) - CSV parsing
+- **markdown-it** (^14.1.0) - Markdown processing with multiple plugins
+
+### Image Processing
+- **html2canvas** (^1.4.1) - HTML to canvas conversion
+- **cropperjs** (^1.6.1) - Image cropping
+- **heic2any** (^0.0.4) - HEIC image conversion
+- **tiff** (^7.1.2) - TIFF image handling
+- **utif** (^3.1.0) - TIFF file utilities
+- **tesseract.js** (^6.0.1) - OCR (Optical Character Recognition)
+
+### UI Components & Icons
+- **@phosphor-icons/web** (^2.1.2) - Icon library
+- **lucide** (^0.546.0) - Icon library
+- **sortablejs** (^1.15.6) - Drag-and-drop sorting
+
+### Internationalization
+- **i18next** (^25.7.2) - Internationalization framework
+- **i18next-browser-languagedetector** (^8.2.0) - Language detection
+- **i18next-http-backend** (^3.0.2) - Translation loading
+
+### Fonts
+- Multiple `@fontsource` packages for web fonts
+
+### Utilities
+- **node-forge** (^1.3.3) - Cryptography
+- **zgapdfsigner** (^2.7.5) - PDF digital signing
+- **archiver** (^7.0.1) - Archive creation
+- **jszip** (^3.10.1) - ZIP file handling
+- **mermaid** (^11.12.2) - Diagram generation
+- **highlight.js** (^11.11.1) - Syntax highlighting
+- **postal-mime** (^2.7.1) - MIME message parsing
+
+## Testing
+
+### Vitest
+- **Version**: ^3.2.4
+- **Configuration**: `vitest.config.ts`
+- **Features**:
+  - Unit testing
+  - UI mode (`@vitest/ui`)
+  - Code coverage (`@vitest/coverage-v8`)
+  - Global test APIs
+  - JSDOM environment (^27.0.1)
+
+### Testing Libraries
+- **@testing-library/dom** (^10.4.1) - DOM testing utilities
+
+## Code Quality & Linting
+
+### ESLint
+- **Version**: ^9.39.2
+- **Configuration**: `eslint.config.mjs`
+- **Plugins**:
+  - `@eslint/js` - Core ESLint rules
+  - `typescript-eslint` (^8.51.0) - TypeScript linting
+  - `eslint-config-prettier` (^10.1.8) - Prettier integration
+
+### Prettier
+- **Version**: ^3.6.2
+- **Configuration**: `.prettierrc`
+- **Features**: Code formatting
+
+### Husky
+- **Version**: ^9.1.7
+- **Usage**: Git hooks
+
+### lint-staged
+- **Version**: ^16.2.7
+- **Usage**: Pre-commit linting
+
+## Documentation
+
+### VitePress
+- **Version**: ^1.6.4
+- **Usage**: Documentation site generator
+- **Framework**: Vue.js ^3.5.26
+
+## Containerization & Deployment
+
+### Docker
+- **Base Images**:
+  - Build: `node:20-alpine`
+  - Production: `nginx-unprivileged:stable-alpine-slim`
+- **Configuration**: `Dockerfile`, `docker-compose.yml`, `docker-compose.dev.yml`
+- **Web Server**: Nginx
+
+### Kubernetes
+- **Tool**: Helm
+- **Configuration**: `chart/` directory
+- **Chart Version**: 0.2.0
+
+### Cloudflare Workers
+- **Configuration**: `cloudflare/wrangler.toml`
+- **Workers**: CORS proxy, WASM workers
+
+## WebAssembly (WASM)
+
+- **qpdf.wasm** - PDF processing
+- **pdfium.wasm** (embedpdf-snippet) - PDF rendering
+- **pdfjs-viewer/wasm/** - PDF.js WASM modules
+  - `qcms_bg.wasm` - Color management
+  - `openjpeg.wasm` - JPEG2000 support
+
+## Web Workers
+
+Custom workers for async PDF processing:
+- `add-attachments.worker.js`
+- `edit-attachments.worker.js`
+- `extract-attachments.worker.js`
+- `alternate-merge.worker.js`
+- `json-to-pdf.worker.js`
+- `pdf-to-json.worker.js`
+- `merge.worker.js`
+- `table-of-contents.worker.js`
+
+## Development Tools
+
+### Version Control
+- **Git** - Source control
+- **GitHub Actions** - CI/CD workflows
+
+### Build Scripts
+- Custom Node.js scripts in `scripts/` directory
+- Version management
+- Release automation
+- i18n page generation
+- Sitemap generation
+- Documentation building
+
+## Runtime Environment
+
+- **Target**: Modern browsers with ES2022 support
+- **DOM APIs**: DOM, DOM.Iterable, WebWorker
+- **Module System**: ES Modules (ESM)
+- **Compression**: Gzip and Brotli support
+
+## Security
+
+- **CORS Headers**: Cross-Origin security policies
+- **Content Security**: COOP and COEP headers
+- **Cryptography**: node-forge library
+- **Digital Signatures**: zgapdfsigner
+
+## License
+
+- **AGPL-3.0-only**