ESLint and Prettier: Code Quality and Formatting

Set up ESLint 9 flat config and Prettier to catch bugs and format code automatically. For JavaScript and TypeScript teams.

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What you'll learn

  • Explain what ESLint and Prettier each do and how they differ.
  • Write an ESLint flat config and a Prettier configuration.
  • Integrate the two tools without rule conflicts, with editor support.
  • Enforce checks with Husky, lint-staged and CI.
  • Share configs, lint TypeScript and migrate from legacy .eslintrc files.

Syllabus

Module 1: Getting Started

  1. Introduction to Code Quality Tools

Module 2: Foundation & Setup

  1. Installation & Project Setup
  2. ESLint Flat Config Basics
  3. Prettier Configuration
  4. Integrating ESLint and Prettier

Module 3: Core Concepts

  1. Understanding ESLint Rules
  2. Popular ESLint Plugins

Module 4: Configuration Deep Dive

  1. Targeting Files, Globals & Overrides
  2. Prettier Advanced Options

Module 5: Code Quality & Best Practices

  1. Common Code Quality Issues
  2. Formatting Standards & Team Consistency

Module 6: Practical Applications

  1. Fixing Issues Automatically
  2. Integration with Editor / IDE

Module 7: Advanced Quality Control

  1. Pre-commit Hooks & Husky
  2. Custom ESLint Rules

Module 8: Integration & CI/CD

  1. CI/CD Pipeline Integration
  2. Team Setup & Shared Configurations
  3. Reporting & Performance
  4. Linting TypeScript with typescript-eslint
  5. Alternatives: Biome and oxlint

Module 9: Advanced Topics

  1. Migrating Between ESLint Versions
  2. Debugging Linting Issues

Module 10: Final Review & Mastery

  1. Best Practices & Anti-patterns
  2. Real-world Project Examples
  3. Interview Questions & Cheat Sheet
  4. Troubleshooting & Common Gotchas
  5. Summary & Next Steps