Open Mercato: What it is and why we implement it for clients?

1. What is Open Mercato?

Open Mercato is a framework for building business applications. Its key features include ready-made modules and mechanisms for managing customers, products, orders, and inventory, as well as automating processes. Development teams can use this foundation to build a solution that reflects how a particular company operates.

The Open Mercato core is an open source project released under the MIT license. The framework uses TypeScript and Next.js, technologies widely used in modern web application development.

Open Mercato can provide the foundation for a CRM, ERP, or OMS (Order Management System), or for a solution that combines functions from several types of business systems. The scope depends on the processes it needs to support and the modules used in the project. Open Mercato’s functionality can expand as the project develops. A company can start with a selected process, such as order management, and then extend the solution to cover additional areas.

2. How can Open Mercato reduce the work required to build a custom system?

Building a custom ERP system has traditionally required considerable work on the basic mechanisms of a business application, including user and permission management, data management, and interfaces. Open Mercato provides a ready-made technical foundation that allows the team to focus sooner on processes specific to the organization.

Open Mercato is being developed as an AI-native framework, providing documentation and instructions for AI-assisted application development and supporting collaboration with AI agents through Model Context Protocol (MCP). The choice between software as a service (SaaS), a framework-based solution, and building from scratch depends on the company’s processes, required integrations, and expected level of control over the system.

3. What makes Open Mercato stand out from traditional ERP and CRM systems?

Open Mercato gives development teams a foundation for building an application around an organization’s processes. A company can select the modules it needs, extend the data model, add its own logic, and connect the solution to its existing IT environment.

From our perspective, three elements are particularly relevant: modular architecture, an open licensing model, and the ability to integrate with systems responsible for product data and digital channels.

3.1 Overlay architecture: Keeping custom extensions separate from the core

One reason we became interested in Open Mercato is the way it separates the framework’s core from extensions developed for individual clients.

The overlay mechanism, a layer of extensions kept separate from the core, allows developers to place custom modules and modifications outside the core code. Business logic specific to a company can therefore be developed in a separate layer. Core updates then have less impact on the code written for the client. This matters in systems developed over several years. A company can add processes and integrations while maintaining a clear distinction between the core components and its custom extensions. After an update, custom extensions still need to be checked for correct operation, particularly when modifications are extensive.

The ability to connect Open Mercato with a PIM system is especially relevant to us. Product information can remain in the PIM system, while Open Mercato handles business processes that use that data. For projects requiring a complex product data model, we can draw on our experience with PIM and Pimcore implementations.

3.2 MIT licensing and greater freedom to choose a technology partner

The Open Mercato core is released under the MIT license. This allows its code to be used, modified, and extended in commercial projects under the license terms. Enterprise modules are covered by a separate commercial license. For clients, this means that a team of their choice can maintain and develop the solution’s code. The system can run on infrastructure and use services selected to meet the project’s requirements.

The open licensing model gives companies greater flexibility when changing technology partners or deciding how to maintain the system. The degree of independence also depends on other parts of the architecture, such as cloud services, integrations, and external components.

The Open Mercato core is available under the MIT license without per-user fees. The commercial Enterprise subscription is billed per project, also without a limit on the number of users. Implementation costs include solution development, infrastructure, maintenance, and any commercial services or components used.

4. Why Tandemite chose Open Mercato

At Tandemite, we have worked for years with PIM systems, including Pimcore, as well as headless content management systems, which separate content from its presentation, e-commerce solutions, and B2B platforms. In these projects, product data, prices, and inventory levels are stored in different systems. Sales operations require this information to move reliably between them.

Open Mercato fits this architecture because it can work with PIM as a source of structured product data, alongside e-commerce systems and other business applications.

PIM can manage detailed product information, while Open Mercato handles processes involving customers, orders, inventory, and other business areas. Integration takes place through application programming interfaces (APIs), allowing each system’s responsibilities to be defined during architecture design.

Another reason is the ability to develop the solution in stages. A client can start with a process that currently creates difficulties in day-to-day work and add modules as new needs arise.

The approach to system design also matters. In our projects, we analyze processes, data, user needs, and required integrations. We select technologies based on those findings. Open Mercato’s modular architecture allows us to maintain this approach as the solution continues to develop.

Our teams’ experience with TypeScript and Next.js also supports the choice of Open Mercato. Both technologies are widely used in web application development.

5. Open Mercato use cases: Which companies and projects can benefit?

Open Mercato is worth considering where a system needs to support nonstandard business processes. B2B projects are a good example, particularly when a company has its own way of managing orders, quotes, customers, or distributors. These processes may require individual pricing rules, additional approval stages, support for an unusual organizational structure, or integration with industry-specific systems. The framework allows developers to reflect these rules in the application’s logic.

Another use case involves organizations that manage a single process through multiple SaaS applications, spreadsheets, and custom automations. Open Mercato can provide a shared application layer for a selected business area and integrate data from existing systems.

Projects in which a custom data model and the ability to extend it have strategic importance are another relevant use case. These include organizations with extensive product catalogs, multiple sales channels, and processes that connect PIM, e-commerce, ERP, and CRM.

Open Mercato can also provide the foundation for new digital products whose business logic will change as the product develops.

6. Is Open Mercato worth implementing? Our take

Open Mercato is an interesting option for organizations that need a system tailored to their processes and expect to continue developing it. It is particularly suited to projects that require custom business logic, integrations, and control over code and data.

The framework is young, so its maturity, pace of development, documentation quality, and the availability of specialists who can maintain and extend the solution should all be considered. Implementation requires a development team. The project needs a data model, integrations, permissions, a deployment process, monitoring, tests, and an update strategy. The scope of this work depends on the company’s processes and existing IT environment.

Companies that need standard features and want to launch a system quickly may find ready-made SaaS, ERP, or CRM solutions more suitable. Open Mercato is worth considering when a system needs to support company-specific processes and connect with other applications. To assess whether implementing Open Mercato makes sense, we first analyze the processes the system will support. We then check whether its options for adapting functionality and integrations meet the company’s needs.

7. What does implementing Open Mercato with Tandemite look like?

We begin an Open Mercato implementation by defining the business area and the data needed to support it. We analyze existing systems, define who is responsible for the data, identify user needs, and determine the required integrations. These findings determine the scope of the first stage. We specify the Open Mercato modules, custom extensions, data model, and interfaces for exchanging information with the client’s PIM, ERP, e-commerce, or other systems.

The next stage involves building the solution and testing it against examples of actual user activities. We check data flows between systems, user permissions, error handling, and the processes that will move to the new application.

Once the first version is live, additional modules can be introduced and the system extended to support further processes. This approach connects technology development with specific business needs and the results of each project stage.

If you are considering implementing Open Mercato, contact us. Together, we can analyze the processes the system needs to support and its place in your existing IT architecture.