30 open-source projects similar to polarsource/polar, ranked by shared indexed features. Tags may describe platforms or build tools rather than the same primary purpose. Check each project’s use case, license, and deployment requirements before treating it as a replacement.
Lago is an open-source billing platform designed for managing subscriptions, usage-based metering, and automated invoicing. It functions as a comprehensive system for defining pricing plans, tracking real-time consumption via a metering engine, and controlling feature entitlements based on active customer subscriptions. The platform differentiates itself through a dynamic billing engine that supports hybrid pricing models and a credit-based wallet system for managing prepaid funds. It includes specialized tools for multi-tenant entitlement mapping, allowing operators to tie specific product p
Kill Bill is a subscription billing platform and usage-based billing engine designed to manage recurring invoicing and automated payment collection. It functions as a multi-tenant billing infrastructure, providing isolated environments for different organizational entities through a dedicated API. The system is distinguished by a plugin-based extension framework that allows for the integration of third-party payment gateways and custom business logic. It includes a payment gateway orchestrator to handle transactions and refunds, as well as a revenue recognition system to allocate contract rev
The stripe-php library is a PHP client used to integrate Stripe payment processing, subscription billing, and financial services into applications. It provides a programmatic interface for managing connected accounts, issuing virtual cards, and automating payouts to sellers. The library distinguishes itself through a comprehensive suite of billing and payment tools, including support for recurring charges, usage-based billing, and the management of customer self-service portals. It further enables financial automation via tax and revenue libraries that handle global sales tax calculation and
Akaunting is a modular business enterprise resource planning system and self-hosted accounting software. It provides a comprehensive platform for small business financial management, centering on a double-entry bookkeeping system with a general ledger and chart of accounts. The platform is designed for extensibility through a module-based architecture and a dedicated marketplace for procuring third-party applications. It supports multi-tenant data isolation and utilizes role-based access control to manage granular user permissions. Its capability surface covers a wide range of business opera
The AWS Cloud Development Kit is an infrastructure-as-code framework that enables developers to define and provision cloud resources using familiar programming languages. By utilizing construct-based synthesis, it translates high-level, object-oriented code into declarative templates, allowing for the automated management of complex cloud environments through a centralized, code-driven control plane. The framework distinguishes itself through its ability to model infrastructure as a dependency-aware resource graph, ensuring that components are provisioned and updated in the correct order. It
Invoice Ninja is a professional billing and invoicing platform designed for managing clients, projects, and financial records. It serves as a multi-currency billing system and time tracker available as both a cloud-based application and a self-hosted suite. The platform distinguishes itself through comprehensive support for regional taxes, diverse currency formats, and automated exchange rate updates. It includes dedicated cross-platform mobile and desktop applications to manage business data across different operating systems. The software covers the end-to-end financial lifecycle, includin
This project is a type-safe web application template and admin dashboard starter built with Next.js, TypeScript, and the shadcn/ui component library. It serves as a multi-tenant SaaS boilerplate designed for developing administrative interfaces and software-as-a-service applications. The starter distinguishes itself through integrated SaaS infrastructure, including multi-tenant workspace management, organization-level permissions, and subscription billing integration. It features role-based access control to gate specific pages and navigation items based on user roles or subscription tiers.
WooCommerce is a comprehensive eCommerce framework for WordPress that transforms websites into fully functional online stores for physical and digital goods. It serves as a digital storefront manager for product catalogs, inventory, and customer orders across retail and wholesale business models. The system functions as a payment gateway integrator, connecting shops to diverse processors for credit cards, digital wallets, and subscriptions. It also operates as an order fulfillment system for calculating shipping rates, generating labels, and coordinating delivery via third-party couriers, whi
Big Capital is a cloud accounting management system designed to track assets, liabilities, and equity through a digital ledger. It provides a multi-tenant organizational framework that supports multi-branch tracking and regional currency settings. The system distinguishes itself through integrated bank feed management, utilizing secure token exchanges and webhook processing for automated transaction synchronization and rule-based categorization. It also features a multi-currency ledger that handles base currency conversions and specific currency codes. The platform covers comprehensive finan
Blynk is an embedded device framework and IoT cloud connectivity library designed to establish secure, bi-directional communication between microcontrollers and a remote management platform. It provides the core identity of an IoT device management tool, enabling the synchronization of device states, remote hardware control, and the mapping of hardware data to cloud-based interfaces. The project distinguishes itself through a virtual-pin system that decouples cloud communication from physical pins, allowing for hardware-independent data exchange. It also supports advanced architectural offloa
GAM is a command-line tool for administering Google Workspace and Cloud Identity. It translates command-line arguments into structured API calls, enabling administrators to manage users, groups, organizational units, and domain settings across a Google Workspace environment. The tool handles authentication through OAuth2 flows, service accounts, and workload identity federation, and supports multi-tenant configurations for managing multiple domains or cloud projects from a single installation. GAM distinguishes itself through its batch processing and automation capabilities. It can process la
InsForge is a backend-as-a-service platform that provides an integrated suite of tools for managing relational databases, identity provision, object storage, and serverless compute. It functions as an open-source identity provider and a PostgreSQL database manager featuring integrated vector storage and row-level security. The platform serves as an LLM orchestration gateway, offering a unified endpoint to route requests across various AI providers through an OpenAI-compatible interface. It enables AI-driven application generation and connects AI agents to backend resources using a standardize
LibSQL is a high-performance, distributed SQL database engine that extends SQLite to support remote network access, edge computing, and real-time synchronization. It functions as an embedded database library that integrates directly into application processes while providing the infrastructure to maintain consistency across multiple geographic regions. The platform distinguishes itself by enabling database interaction over standard HTTP protocols, allowing applications to query remote data sources in serverless and edge environments without requiring local filesystem access. It includes nativ
This project is a Next.js SaaS starter kit and billing boilerplate designed for building subscription-based software services. It provides a pre-configured foundation that integrates a PostgreSQL database schema with Stripe to manage recurring billing, tiered pricing models, and customer payment portals. The implementation features a synchronization system that uses webhooks to mirror external product data and subscription states into a local relational database. It includes an authentication layer that links external identity providers to user accounts and manages secure session tracking. T
Crater is an open source invoicing software and multi-tenant accounting system. It serves as a financial management tool for creating professional invoices and estimates, tracking business expenses, and managing the financial records of several distinct business entities within a single instance. The platform integrates with payment processors to collect client payments automatically and provides a dedicated billing portal where customers can access their history and pay invoices online. It includes a template-based engine for generating PDF invoices and supports the automation of recurring s
Crater is an invoicing and billing software system designed for creating professional invoices, estimates, and recurring billing schedules. It serves as a multi-entity accounting manager, allowing for the organization and separation of financial data and billing records across multiple different business organizations. The platform integrates payment gateway services to collect funds directly from customers and provides a secure client billing portal where customers can access account details and pay outstanding invoices. It also functions as an expense tracking application to log outgoing co
Agentic is a tool marketplace and management platform designed for the Model Context Protocol. It provides a gateway and proxy that enables the discovery, publishing, and distribution of vetted tools for agentic AI frameworks. The platform specializes in Model Context Protocol monetization, allowing developers to transform services into paid products through integrated authentication, usage-based billing, and subscription management. It also includes a converter that transforms OpenAPI specifications into compatible protocol servers for use in AI workflows. The system covers a broad range of
Aureuserp is a modular open-source enterprise resource planning system and business suite designed to integrate accounting, inventory, manufacturing, human resources, and project coordination into a single centralized database. It functions as a comprehensive platform for managing business operations, sales orders, and procurement. The system uses a modular architecture that allows for the installation or removal of specific feature modules to tailor application capabilities to business needs. It includes a localization layer to translate the user interface into multiple languages and employs
Crater is an open-source invoicing and expense tracking software designed for individuals and small businesses. It serves as a self-hosted billing platform that allows users to monitor the overall financial health of a business by recording professional services rendered and tracking outgoing costs. The system functions as a payment gateway integrator, connecting to third-party providers such as Stripe to process secure transactions for issued invoices. It provides specialized tools for freelance invoice management, including the generation of professional billing documents and cost estimates
Vendure is a Node.js e-commerce engine and headless commerce framework built with NestJS and TypeScript. It serves as a multi-channel commerce platform that manages product catalogs, orders, and customers via a strongly typed GraphQL API. The platform is distinguished by its highly extensible architecture, featuring a customizable administrative dashboard where developers can inject custom React components and entity views. It supports multi-channel commerce, allowing the isolation of products, currencies, and regional catalogs from a single unified backend. The engine covers a broad range o
Paymenter is an open-source hosting automation platform designed to manage the lifecycle of digital services and infrastructure. It provides a centralized system for hosting providers to handle customer account administration, recurring subscription billing, and the automated provisioning of virtual, dedicated, and game-specific server instances. The platform distinguishes itself through a modular architecture that supports extensive customization and third-party integrations. By utilizing a plugin-based system and standardized interface layers, it allows providers to adapt core business logi
Wdc-saas-starter-kit is a full-stack Next.js and TypeScript web application boilerplate designed to launch subscription-based software products. It comes pre-configured with a relational database ORM layer, user authentication, role-based access control, and cloud object storage integrations for handling user-uploaded files and media. The starter kit features recurring subscription management and payment webhook processing through an integrated payment gateway to synchronize customer billing cycles, plan upgrades, and subscription statuses. It also includes multi-tenant team workspace archit
Stack is an open-source identity provider that manages user authentication, passkeys, and OAuth tokens. It provides an identity infrastructure that handles user data storage and authentication flows via a centralized administrative dashboard. The platform differentiates itself by integrating a multi-tenant user management system that organizes users into team workspaces through invitation flows. It includes a secure secret vault for storing encrypted API keys and user tokens using encryption keys that remain hidden from the service provider. The system covers a broad range of administrative
This project is an AI model API gateway and proxy server designed to provide a unified interface for interacting with diverse artificial intelligence service providers. It functions as a centralized middleware platform that routes, load balances, and translates API requests across multiple models, enabling developers to access text, image, audio, and video generation capabilities through a single, standardized integration. The gateway distinguishes itself through comprehensive administrative and financial controls, including event-driven usage accounting, real-time token consumption tracking,
Geekai is a multi-model AI platform and SaaS framework designed to deploy and manage AI agents and multimodal models through a unified interface. It serves as a multimodal AI gateway, providing centralized access to large language models and generative tools for text, image, audio, and video production. The project functions as an AI agent orchestrator, allowing for the definition of specialized personas and the import of external workflows and knowledge bases. It distinguishes itself by providing a complete commercial service layer, including credit-based billing, subscription management, an
CRMEB is a comprehensive e-commerce platform built on ThinkPHP 6, designed as a headless system that delivers standardized APIs to various frontend clients. It provides a unified backend to synchronize product catalogs, orders, and customer data across web browsers, mobile applications, and mini-programs. The platform supports diverse commerce models, including multi-vendor marketplaces where independent merchants manage their own stores, centralized chain store networks, and social commerce frameworks featuring affiliate distribution and community group buying. It also integrates specialized
Kimai is an open-source time tracking system that records employee working hours, manages absences, and generates professional invoices from recorded timesheets and expenses. It organizes all time records through a mandatory three-level hierarchy of customer, project, and activity, and supports project budget monitoring with configurable time and money limits. The application is extensible through a plugin system that allows adding custom features, invoice templates, reporting views, and dashboard widgets without modifying core files. It provides a RESTful JSON API for programmatic read and w
Apollo Universal Starter Kit is a full-stack application boilerplate and starter template designed to accelerate cross-platform development across web, mobile, and server environments. It provides a modular architecture that organizes code into independent, self-contained feature directories, combined with a GraphQL-driven data layer and a server-side rendering pipeline to optimize performance and search engine optimization. The project incorporates compile-time code generation tooling to automatically scaffold schemas, resolvers, and components, alongside a real-time subscription engine for
This project is a comprehensive link management and marketing attribution platform designed for creating, tracking, and analyzing shortened URLs. It functions as a centralized hub for marketing analytics, providing tools to monitor link performance, visualize conversion funnels, and manage affiliate programs through a unified dashboard. The platform distinguishes itself by integrating advanced attribution modeling and partner management directly into the link infrastructure. It supports complex marketing workflows, including automated commission calculations, fraud detection, and payout distr
Lens is a multi-cluster management platform and desktop application for administering Kubernetes environments. It provides a graphical interface for deploying Helm charts, editing YAML manifests, and managing the lifecycle of pods and deployments. The project features an AI-powered cluster assistant that enables users to query cluster state, perform autonomous troubleshooting, and translate natural language requests into system commands. It also supports collaborative team access through shared spaces, utilizing encrypted cluster sharing and role-based access control to manage credentials and