Exploring Codebases

Use Gemini CLI to understand and analyze existing code projects

Beginner⏱️ 15 minutes

What You'll Learn

  • How to analyze project architecture and structure
  • Understanding code relationships and dependencies
  • Identifying security mechanisms and patterns
  • Effective prompting techniques for code analysis

Prerequisites

Completed Getting Started Tutorial

You should have Gemini CLI installed and authenticated on your system.

Access to a Codebase

Any existing project directory - your own code, an open-source project, or a cloned repository.

Setting Up for Code Exploration

Navigate to Your Project

Gemini CLI works best when run from within a project directory. It can analyze the current directory and its subdirectories to understand your codebase structure.

1. Navigate to your project directory:

cd /path/to/your/project

2. Start Gemini CLI:

gemini

Tip: Gemini CLI can work with projects of any size, from small scripts to large enterprise applications. It uses Gemini's 1M+ token context window to analyze extensive codebases.

Understanding Project Architecture

High-Level Overview

Start with broad questions to understand the overall structure and purpose of the codebase:

Example Prompts:

> Describe the main pieces of this system's architecture.
> What is the primary purpose and functionality of this application?
> How is this project organized? What are the main directories and their purposes?

Technology Stack Analysis

Understand what technologies, frameworks, and libraries the project uses:

Example Prompts:

> What programming languages and frameworks are used in this project?
> What are the main dependencies and external libraries?
> How is the build and deployment process configured?

Security and Best Practices Review

Security Mechanisms

Analyze the security measures and patterns implemented in the codebase:

Security Analysis Prompts:

> What security mechanisms are in place?
> How is user authentication and authorization handled?
> Are there any potential security vulnerabilities or areas for improvement?

Understanding Code Relationships

Component Interactions

Explore how different parts of the codebase interact with each other:

Relationship Analysis:

> How do the main components communicate with each other?
> What is the data flow through the application?
> Which files or modules are most central to the application's functionality?

Specific File Analysis

Dive deeper into specific files or components:

Targeted Questions:

> Explain what the main.js file does and how it fits into the overall architecture.
> What is the purpose of the utils directory and its contents?
> How does the database layer interact with the business logic?

Effective Analysis Techniques

✅ Do's

  • Start with broad, high-level questions
  • Ask follow-up questions for clarification
  • Focus on understanding patterns and conventions
  • Inquire about testing and documentation practices
  • Ask about deployment and configuration

❌ Don'ts

  • Don't ask overly specific questions initially
  • Avoid making assumptions about the codebase
  • Don't focus only on individual lines of code
  • Avoid asking about proprietary business logic
  • Don't expect instant understanding of complex systems

Next Steps

🎉 Great Work!

You now know how to effectively analyze and understand codebases using Gemini CLI. Ready to take it further?