polyrepos

Polyrepos, short for multiple repositories, is a software development organization pattern in which code for a system is distributed across several repositories rather than stored in a single repository (monorepo). In a polyrepo approach, each project, service, library, or component typically has its own version control repository, with ownership and access controls managed separately.

Characteristics of a polyrepo model include autonomous histories, independent release cycles, and separate continuous integration pipelines for each repository. Teams own specific repos, and dependencies between components are managed through package managers, versioned libraries, or lightweight submodules. Cross-repo changes often require coordination across teams, and discovering and understanding the overall system can be more challenging compared to a single, centralized codebase. Governance and tooling must support multiple repositories, standardized interfaces, and consistent release practices.

Advantages of polyrepos include greater autonomy for teams, more granular access control, and smaller, faster repositories. Independent versioning and release cycles can reduce blast radius when changes are made, and targeted CI pipelines can improve feedback times. It can also better align with organizations that have diverse tech stacks or separate business units.

Disadvantages include the complexity of coordinating changes across repositories, managing dependencies and compatibility, and maintaining consistency in coding standards and API contracts. Integration testing and end-to-end workflows can become more involved, and there is often increased overhead in governance, tooling, and onboarding new contributors.

Practices commonly associated with polyrepos include clear API contracts and semantic versioning, internal package registries or dependency catalogs, automated pipelines for each repository, and explicit change coordination processes for cross-repo updates. Polyrepos are often contrasted with monorepos, which centralize code to ease cross-cutting changes but can face scaling challenges in very large organizations.