Modulebymodule

Modulebymodule is a software design concept and accompanying toolset aimed at organizing complex software systems as a collection of self-contained modules, each with a clearly defined interface. In this approach, development proceeds module by module, with explicit contracts governing inputs, outputs, and behavior, enabling independent evolution and substitution of components without affecting other parts of the system.

Modules are the primary unit of development; they can be versioned independently; the dependency graph is defined in terms of interfaces rather than concrete implementations. A module may include its own tests, documentation, and deployment artifacts. Build tools or orchestrators coordinate cross-module integration, ensuring compatibility at the interface level.

Common practices include semantic versioning for modules, lightweight packaging, and a central registry or manifest that records available modules and their interfaces. In practice, modulebymodule aligns with ideas from modular monoliths, package-based dependency management, and monorepos, but emphasizes module autonomy and interface-driven development.

Benefits include improved maintainability, parallel development, clearer responsibility boundaries, and easier testing; challenges include coordination overhead, potential version drift, and the need for robust interface design and governance.

While not a universally adopted standard, modulebymodule informs contemporary architectural discussions around modularity, plug-in architectures, and scalable software composition.