Open source e-commerce and marketplace platform on the JVM.
Note: This project is retired as of 2017. It is no longer actively developed, though production sites still run on it. The repository remains as a reference.
Running an online store or a multi-vendor marketplace shouldn't require a monolithic CMS or assembling a dozen services. Mayocat Shop is a self-contained platform that one person can deploy easily and a non-technical merchant can operate.
It ships as a single JAR that can be pointed at a PostgreSQL database with a theme dropped in to get a store running — back-office, storefront, and REST API included.
E-commerce platform with content management and multi-vendor marketplace support:
- Run one store or many — multi-tenancy is built in. Each storefront gets its own catalog, configuration, theme, and data from a single deployment.
- Sell things — products with variants, collections, cart, checkout, payment (PayPal and extensible), shipping (flat rate, weight-based, price-based), taxes, orders, invoicing.
- Manage content — pages, blog, home page curation. The CMS is a first-class citizen next to the catalog.
- Customize without coding — theme system with HTML templates and a declarative addon system. Need a color picker on your products? Declare it in your theme config, it shows up in the back-office.
- Integrate — REST API for every entity, webhooks for order and payment events, Elasticsearch-powered search.
- Localize — multi-language product content, locale-aware configuration.
 Product editing with rich text, image gallery, and inventory management |
 Order management with status tracking, line items, and shipping |
A few storefronts built on the platform — each with its own theme, branding, and content:
 Doolittle — children's magazine and shop |
 This is not a map — travel photography books |
 Aristide — cat hotel in Paris, with booking, blog, and content pages |
A few things that shaped the architecture:
Platform and domain are separate. A reusable platform layer (accounts, configuration, theming, search, storage, multi-tenancy) and the e-commerce domain (catalog, cart, checkout, payment, shipping) don't know about each other. The platform could host a different application entirely.
Multi-tenancy is structural. Not a filter on queries — it goes through the configuration system (which merges defaults, theme settings, and per-tenant overrides), request handling (tenant resolution from hostname or path), and data access. A marketplace operator sets global defaults; each tenant customizes from there.
Extensibility through declaration. Theme authors define custom fields — selects, checkboxes, color pickers, dates — in YAML. The platform renders them in the back-office, stores them, indexes them. No plugins to write.
Lightweight by choice. Dropwizard and XWiki's component manager instead of heavier frameworks. Fast to start, easy to follow, explicit module boundaries.
mayocat-shop/
├── platform/ Reusable infrastructure (27 modules)
│ accounts, multitenancy, configuration, store,
│ search, themes, addons, webhooks, rest,
│ image, mail, pdf, localization, ...
│
├── shop/ E-commerce domain (14 modules)
│ catalog, cart, checkout, payment, billing,
│ customer, shipping, taxes, marketplace, ...
│
└── cms/ Content management (4 modules)
pages, news, contact, home
Built with Java, Dropwizard, PostgreSQL, Elasticsearch, and AngularJS — about 50,000 lines of Java across 40+ modules, developed over 2012–2017 in roughly 1,700 commits.
Licensed under MPL 2.0.
- Jérôme Velociter — author and primary developer
- Louis Béziau — back-office UX design
- Johann Pardanaud — back-office localization system, bug fixes
- Vincent Velociter — date handling patches