Frappe Books is a full-featured, offline-first desktop accounting and inventory management application built with Electron, Vue 3, and a custom ORM framework (fyo) on top of SQLite. It supports double-entry bookkeeping, invoicing (Sales/Purchase/Returns), payment processing, stock management (batches, serial numbers, FIFO valuation), Point of Sale (classic and modern layouts), financial reports (Balance Sheet, P&L, Trial Balance, General Ledger, GST reports), loyalty programs, pricing rules, coupon codes, and multi-currency. The architecture is schema-driven: JSON schema files define document structures, and model classes add business logic via formulas, validations, and lifecycle hooks. The backend runs in the Electron main process and exposes IPC APIs for file operations, database access, and auto-updates. The frontend is a reactive Vue 3 SPA with a comprehensive component library. Regional support (India, Switzerland) is implemented through model overrides and schema extensions. The codebase demonstrates strong engineering practices with a layered architecture, but the custom framework introduces some coupling. It is actively maintained with CI/CD, automated tests, and regular patches.
InvoicePrinter is a Ruby library for generating PDF invoices, with additional CLI and HTTP server interfaces. It takes structured invoice data (as Ruby objects or JSON) and generates formatted PDF documents using the Prawn library. The system consists of three main components: the core library for PDF generation, a command-line executable for direct use, and a server executable providing a HTTP API. The architecture shows good separation of concerns with distinct modules for data models, PDF rendering, font handling, and server interface.
Akaunting is a self-hosted accounting and invoicing platform for small businesses and freelancers. It manages invoices, bills, banking transactions, transfers, reconciliations, multi-currency, multi-tax, recurring documents, and financial reports. It includes a customer portal for invoice viewing and payment, and supports multi-company, multi-user with role-based permissions. The system is highly internationalized with 40+ language locales. The architecture is built on a custom PHP framework (Illuminate) that extends Laravel conventions. It uses an event-driven architecture with domain events, listeners, and a job queue for async processing. The frontend combines Blade templates, Vue.js components, and Livewire for interactivity. Multi-tenancy is achieved through company scoping via a global query scope. The system is extensible via a module system with an app store, and includes a CLI for maintenance tasks. Key entry points include the installation wizard (controllers under Install/), authentication flows, and core CRUD controllers for sales, purchases, banking, and settings. Data flows typically involve controllers dispatching jobs that emit events, which listeners handle to update related entities, send notifications, or trigger side effects. Reports use a filter/group/rows event system for extensibility. Import/export is handled via Excel with multi-sheet support. External dependencies include PHP 8.1+, Node 18-20, and a database (MariaDB, MySQL, PostgreSQL, SQLite). It uses Laravel Mix for asset compilation, integrates with payment gateways, email services, and error trackers (Sentry, Bugsnag), and relies on a module marketplace at api.akaunting.com.
Kimai is a self-hosted, open-source time-tracking application built with PHP 8.3+ and Symfony 6/7. It provides a full-featured web interface and REST API for recording timesheets, managing projects/customers/activities, generating invoices, exporting data (PDF, XLSX, CSV, HTML), and producing reports. The architecture follows a classic Symfony monolith with Doctrine ORM, Twig templating, and Webpack Encore for frontend assets. It supports multi-user, multi-timezone, multi-language, LDAP/SAML authentication, two-factor authentication, and a plugin system via tagged services and compiler passes. The codebase is heavily event-driven, with over 70 domain events and subscribers, and includes a rich set of dashboard widgets, custom form types, and validation constraints. The repository is actively maintained with frequent commits, extensive test coverage (PHPUnit), and continuous integration pipelines.
Invoice Ninja is a full-featured open-source invoicing and billing platform designed for small to medium businesses. It handles the complete lifecycle of invoices, quotes, credits, purchase orders, payments, and expenses. The system supports multi-tenant SaaS and self-hosted deployments with per-company database isolation, and integrates with over 20 payment gateways (Stripe, PayPal, Mollie, GoCardless, etc.). It provides client and vendor portals for self-service, along with extensive reporting, CSV export, and e-invoicing capabilities (Peppol, Verifactu, France e-reporting). The application follows a monolithic MVC architecture built on a custom PHP framework (Illuminate) similar to Laravel. It uses an event-driven architecture with domain events and listeners for side effects (email, webhooks, activity logging). Background jobs are queued for async processing. The frontend uses Blade templates, Livewire components, and a separate React app for some admin panels. The API is RESTful with OpenAPI documentation. Key entry points are HTTP controllers under app/Http/Controllers, with request validation classes. Core data flows involve creating entities through factories, persisting via repositories, and triggering events that listeners handle. Payment flows go through abstract payment drivers that encapsulate gateway-specific logic. The system also includes extensive reporting, CSV export, and e-invoicing (Peppol, Verifactu, France e-reporting). External dependencies include a relational database (MySQL/PostgreSQL), Redis for caching and queues, Elasticsearch for search, and various third-party APIs for payment processing, tax calculation (ZipTax), bank integration (Nordigen, Yodlee), email delivery (Mailgun, Postmark, Brevo), and e-invoicing gateways (Storecove, Qvalia).
IDURAR is a free, open-source ERP and CRM application built on the MERN stack (MongoDB, Express.js, React.js, Node.js) with Ant Design and Redux. It provides modules for invoice management, payment processing, quote generation, customer relationship management, inventory tracking, and financial reporting. The system features multi-language support (44 languages), PDF generation for business documents, role-based access control, and a responsive user interface. The architecture separates concerns with a RESTful API backend and a modular frontend utilizing React, Redux for state management, and Ant Design for UI components.
This repository is a collection of Odoo Community Association (OCA) addons focused on extending accounting and invoicing functionality in Odoo. It provides over 50 modules that automate invoice processing, manage taxes and discounts, handle refunds and returns, integrate stock operations with invoicing, and enhance partner-specific invoicing workflows. Each module follows standard Odoo module structure with models, views, wizards, and data files, extending core Odoo models like account.move, sale.order, and stock.picking via inheritance. The modules are loosely coupled but may have interdependencies declared in their manifests. The system is designed to be installed within an Odoo instance, with entry points defined in each module's __init__.py and __manifest__.py files. Recent activity (last commit 2026-09-25) and active maintenance indicate a healthy project, though the wide version support (some modules targeting Odoo 9.0c-18.0) requires careful dependency management.