Section 1.1: What Is a Monorepo?

A monorepo, or single repository, means that all source code is stored in one Git repository. This setup encourages collaboration among team members since everyone contributes to the same codebase, which can house multiple applications.

Section 1.2: What Is a Polyrepo?

In contrast, polyrepos consist of separate repositories for each application. Teams manage their individual repositories, allowing them to establish unique branching strategies and permissions. Many teams opt for polyrepos because they simplify management, albeit at the cost of creating silos.

Section 1.3: Comparing Team Collaboration

Within polyrepos, teams operate in isolation, focusing solely on their repositories. This leads to rapid initial productivity but can hinder visibility and collaboration across teams. The effort needed to maintain various build pipelines and tools adds to the complexity.

Conversely, monorepos require teams to collaborate and adhere to shared coding practices. This visibility fosters cooperation and encourages teams to learn from one another's code quality and patterns.

The video "Monorepo vs Polyrepo: Pros, Cons, and Best Practices" provides a detailed analysis of the advantages and disadvantages of both approaches, which can aid in your decision-making process.

Section 1.4: Build Tools and Quality Gates

Each team in a polyrepo must set up its own build systems and quality gates, leading to duplicated efforts and increased maintenance costs. In a monorepo, these tools can be managed centrally, minimizing redundancy and streamlining processes.

Section 1.5: Flexibility in Management

Polyrepos grant teams substantial flexibility in managing their code, while monorepos intentionally limit this flexibility to promote adherence to best practices across the organization.

Section 2.1: Code Refactoring Challenges

Refactoring code in polyrepos can be labor-intensive, as it requires managing individual repositories separately. Monorepos simplify this process, allowing for bulk changes through atomic commits that cover multiple applications.

Section 2.2: Handling Upgrades

Upgrading shared libraries or tools in a polyrepo falls to individual teams, which can lead to delays. Conversely, monorepos facilitate coordinated upgrades, ensuring all teams benefit from the latest updates simultaneously.

The video "Monorepo VS Polyrepo" offers insights into the upgrade processes of both systems, helping teams to understand the implications of their repository choices.

Section 2.3: Managing Code Size

Polyrepos typically see a gradual increase in code size, while monorepos begin with a larger codebase that can expand significantly as applications grow. This can lead to productivity challenges, as tasks like code checkout, builds, and unit tests take more time in a larger code environment.