Monorepo vs Polyrepo: The Real Factors That Determine the Right Choice at Scale

Choosing between a monorepo and a polyrepo is less a Git decision and more a question of team ownership, dependency management, and architectural boundaries. Engineers working with distributed systems often find that the repository structure itself is rarely the root problem — what matters more is how teams are coupled and how frequently services change together. A monorepo offers a key advantage: the ability to view and modify the entire codebase at once, making large-scale refactors, API contract changes, and dependency upgrades significantly easier to manage. Polyrepos, by contrast, can provide stronger team autonomy and isolation, but may introduce coordination overhead when shared libraries or cross-service changes are involved. Ultimately, the more productive question is not how many repositories to create, but where to draw boundaries between teams, code, and delivery pipelines.