DaxPay Open-Source Payment System
The core of the DaxPay open-source payment platform is released under GNU LGPL v3.0 or later (LGPL-3.0-or-later). It provides payment-core capabilities such as payment and refund, and targets payment service providers, multi-merchant platforms, and cross-border business teams. The core software charges no license fee; use, modification, and distribution must comply with the license and the applicable agreements.
Try It Online
DaxPay provides an online demo environment with ready-to-use accounts, so you can experience the core features without a local deployment. See System Demo.
What Problem It Solves
Integrating multiple pay providers (Alipay, WeChat, UnionPay, etc.) into a business system usually involves:
- Each channel has its own API specification, signature algorithm, and callback mechanism, making integration costly
- Operations, upgrades, and failover across multiple channels are hard to manage in a unified way
- Channel SDK dependency conflicts and version locks couple the payment code tightly with the core business
- Fund reconciliation, risk control, and terminal device management across providers stay fragmented
DaxPay wraps every channel behind a unified HTTP interface: a business system integrates once with a single standard protocol and gains access to multiple pay methods. Third-party SDKs are meanwhile isolated in independently deployed channel sub-apps, which significantly reduces the complexity of integration, operations, and upgrades.
Core Features
- Core payment capabilities — the full transaction loop: pay, refund, transfer, allocation, query, callback, sync, close, and merchant notify
- Multi-merchant mode — admin and merchant dual portals with row-level data isolation
- Unified HTTP interface — channels wrapped behind a RESTful standard protocol; integrate once, work with every channel
- Channel orchestration separated from integration — the main app owns channel routing, strategy orchestration, and configuration management; third-party SDK integration is pushed down into independent sub-apps that support independent deployment, independent upgrades, and elastic scaling
- Secure signing — RSA signatures on API requests and responses against tampering, field-level AES-GCM encryption, and encryption on the whole transport path
- Full client coverage — admin/merchant web consoles, a PC + mobile dual-endpoint H5 gateway, admin and merchant cross-platform apps, and a cashier mini-program compiled for multiple platforms
- Internationalization and time zones — 10 languages (CJK + ASEAN); time fields unified as
timestamptz+OffsetDateTime, stored in UTC - Sandbox / production isolation — deployment-level environment isolation keeps production data clean by design and is enforced at startup
Project Composition
DaxPay is composed of several sub-projects, each in its own git repository:
- Main backend application — payment core, channel routing orchestration, merchant/provider/system administration
- Channel adapter sub-apps — independently deployed microservices that integrate third-party payment channels (channel-one / channel-two / channel-three), deployed and upgraded independently
- Multi-language SDKs — reference implementations of the open-API signing client in five languages: go / java / node / php / python
- Management frontends — admin/merchant web consoles, mobile H5 (PC + mobile), admin and merchant cross-platform apps, and the cashier mini-program
Applicable Scenarios
- Payment service providers / acquiring outsourcing — unified cashier, multi-channel fallback, multi-merchant onboarding, and data isolation
- Multi-merchant platforms / SaaS — every tenant merchant gets its own payment configuration and bills
- Cross-border and international business — multilingual admin consoles, multi-timezone data storage, and international channel integration reserved
- Independent software vendors (ISV) — integrate payment over one unified HTTP interface and cut the cost of multi-channel integration
Delivered and Roadmap
The open-source edition already delivers the complete core payment pipeline and multi-client admin UIs:
- Delivered — admin web console, merchant web console, mobile H5 (PC + mobile), core payment APIs, and transfer plus allocation on the Alipay / WeChat / Douyin direct channels; 20+ channel capabilities and the cross-platform apps are provided through built-in direct channels, extension packages, and the corresponding version notes
- Roadmap — more international payment channels (PayPal, etc.), a settlement center, more aggregate channel integrations, and cashier-scenario product lines (POS system / desktop cashier / cashier app)
Open-Source License
Open-sourced under the GNU Lesser General Public License v3.0 or later, protected and limited by the laws and regulations of the People's Republic of China. The core software charges no license fee; read the user authorization agreement and the open-source license before use — if you do not agree, do not use it.