# Monorepo vs. Polyrepo

When deciding how to store microservices in Git, there are two main approaches:

**1. One Git Repository per Microservice:**

* **Pros:**
    * **Independence:** Each service is independent with its own versioning and deployment cycle.
    * **Isolation:** Changes in one service don't impact others, reducing integration risks.
    * **Clarity:** Clear ownership and focus on specific functionalities.
* **Cons:**
    * **Complexity:** Managing multiple repositories can be cumbersome, especially for large projects.
    * **Duplication:** Shared code needs to be duplicated across repositories, increasing maintenance burden.

**2. Monorepo (Single Repository):**

* **Pros:**
    * **Simplicity:** All code is in one place, easier to manage and maintain.
    * **Shared Code:** Easier to share and manage common code across services.
    * **Visibility:** Provides a holistic view of the entire system.
* **Cons:**
    * **Tight Coupling:** Changes in one service could impact others, requiring careful coordination.
    * **Complexity:** Large repository can become difficult to navigate and track changes.

Choosing the best approach depends on your specific needs and project characteristics. Here are some additional considerations:

* **Project Size:** For smaller projects, the complexity of managing multiple repositories might outweigh the benefits.
* **Team Structure:** Monorepos require strong communication and coordination within the team.
* **Deployment Frequency:** Frequent deployments for individual services might favor separate repositories.

**Handling Multiple Services in a Monorepo:**

* **Clear Directory Structure:** Organize the codebase with distinct directories for each service.
* **Modularization:** Design services to be loosely coupled and minimize dependencies.
* **Dependency Management:** Use tools like Lerna or Yarn Workspaces to manage dependencies between services.

Ultimately, the best approach depends on your specific context and team preferences. Weigh the pros and cons of each approach to determine the best fit for your microservices project.

## Monorepo Tools:

https://github.com/korfuri/awesome-monorepo

While there isn't a single "best" tool for Python monorepos, several options excel in specific areas. Here are some popular choices, each with its strengths:

**1. Poetry:**

* **Strengths:** Poetry is a popular dependency management tool for Python projects, offering features like virtual environments, dependency resolution, and lock files. While not primarily a monorepo tool, it integrates well with other tools and allows managing individual packages within the monorepo.

**2. Pants:**

* **Strengths:** Pants is a powerful and versatile build system designed for large-scale projects. It excels in monorepo management by utilizing static code analysis and offering features like:
    * **Fast and scalable builds:** Leverages caching and optimization techniques to handle complex dependencies efficiently.
    * **Remote execution:** Enables running tasks on remote machines, ideal for distributed environments.
    * **Modularization:** Supports the creation of well-defined, self-contained modules within the monorepo.

**3. Bazel:**

* **Strengths:** Developed by Google, Bazel is a mature open-source build system known for its scalability and flexibility. It offers strong features for monorepo management, including:
    * **Cross-platform support:** Works seamlessly on various operating systems.
    * **Rule-based configuration:** Offers a powerful and flexible way to define build configurations.
    * **Hermetic builds:** Ensures consistent and reproducible builds regardless of the environment.

**4. Earthly:**

* **Strengths:** Earthly is a newer monorepo tool designed specifically for developer experience. It offers a user-friendly syntax similar to Dockerfiles and features like:
    * **Sandboxed builds:** Isolates build environments for better control and consistency.
    * **Remote execution:** Allows running builds on remote machines for optimized resource usage.
    * **Caching:** Implements caching mechanisms to speed up builds.

**Choosing the right tool depends on various factors like:**

* **Project size and complexity:** Larger projects might benefit from Bazel's scalability, while smaller ones could find Pants or Poetry more manageable.
* **Team experience:** Familiarity with specific tools can influence the learning curve and adoption.
* **Desired features:** Consider features like caching, remote execution, and modularization support.

Ultimately, exploring each option based on your specific needs will help you choose the most suitable tool for your Python monorepo project.

