Dependency Upgrade

Master major dependency version upgrades, compatibility analysis, staged upgrade strategies, and comprehensive testing approaches.

When to Use This Skill

• Upgrading major framework versions
• Updating security-vulnerable dependencies
• Modernizing legacy dependencies
• Resolving dependency conflicts
• Planning incremental upgrade paths
• Testing compatibility matrices
• Automating dependency updates

Semantic Versioning Review

MAJOR.MINOR.PATCH (e.g., 2.3.1)

MAJOR: Breaking changes
MINOR: New features, backward compatible
PATCH: Bug fixes, backward compatible

^2.3.1 = >=2.3.1 <3.0.0 (minor updates)
~2.3.1 = >=2.3.1 <2.4.0 (patch updates)
2.3.1 = exact version

Dependency Analysis

Audit Dependencies

# npm
npm outdated
npm audit
npm audit fix

# yarn
yarn outdated
yarn audit

# Check for major updates
npx npm-check-updates
npx npm-check-updates -u  # Update package.json

Analyze Dependency Tree

# See why a package is installed
npm ls package-name
yarn why package-name

# Find duplicate packages
npm dedupe
yarn dedupe

# Visualize dependencies
npx madge --image graph.png src/

Compatibility Matrix

// compatibility-matrix.js
const compatibilityMatrix = {
  react: {
    "16.x": {
      "react-dom": "^16.0.0",
      "react-router-dom": "^5.0.0",
      "@testing-library/react": "^11.0.0",
    },
    "17.x": {
      "react-dom": "^17.0.0",
      "react-router-dom": "^5.0.0 || ^6.0.0",
      "@testing-library/react": "^12.0.0",
    },
    "18.x": {
      "react-dom": "^18.0.0",
      "react-router-dom": "^6.0.0",
      "@testing-library/react": "^13.0.0",
    },
  },
};

function checkCompatibility(packages) {
  // Validate package versions against matrix
}

Staged Upgrade Strategy

Phase 1: Planning

# 1. Identify current versions
npm list --depth=0

# 2. Check for breaking changes
# Read CHANGELOG.md and MIGRATION.md