Subgitter

Subgitter is a framework and set of tooling designed to organize large software projects as a graph of subrepositories. It sits above traditional version control systems to manage how subprojects relate, depend on each other, and are synchronized across teams. By representing repositories as nodes in a directed graph and storing the relationships in a central manifest, Subgitter enables modular development while preserving a coherent overall history.

The concept addresses challenges of scale in multi-team environments, where multiple components evolve independently but must remain compatible. Subgitter typically uses a manifest file that lists each subrepository, its origin, a target revision or tag, and any dependency constraints between subrepositories. A synchronization engine can fetch, update, or publish subrepositories according to the graph, producing reproducible snapshots for builds or deployments.

Key features commonly associated with Subgitter include selective updates of subgraphs, dependency-aware updates to avoid breaking changes, sandboxed workspaces for isolated development, and the ability to roll back a subrepository without affecting unrelated parts of the project. The approach emphasizes maintaining clear boundaries between components and providing visibility into inter-component dependencies.

Architecture-wise, Subgitter adds a graph layer to the underlying version control system. The manifest serves as the single source of truth for subrepositories, their revisions, and constraints. The system may include tooling to validate the graph, resolve transitive dependencies, and ensure that combined changes remain consistent.

Use of Subgitter is typical in large organizations or projects with modular architectures, such as polyrepo setups, plugin ecosystems, or microservice front-ends, where teams require parallel development without sacrificing integration guarantees. Limitations include added complexity, potential tooling friction with existing workflows, and the need to maintain the manifest and graph accurately. See also: submodules, subtrees, monorepo, dependency management.