dependency-conflict-resolver

Dependency Conflict Resolver

Untangle and resolve package dependency conflicts.

When to Use

• Package installation fails
• Peer dependency warnings
• "Module not found" errors
• Duplicate package warnings
• Version mismatch errors
• Lock file conflicts

Common Error Types

1. Peer Dependency Conflicts

npm WARN ERESOLVE unable to resolve dependency tree
npm WARN peer react@"^17.0.0" from [email protected]
npm WARN   peer react@"^18.0.0" from [email protected]

Cause: Two packages require different versions of the same peer dependency.

2. Version Conflicts

npm ERR! Could not resolve dependency:
npm ERR! peer typescript@">=4.0 <5.0" from [email protected]
npm ERR! node_modules/some-package
npm ERR!   some-package@"^1.0.0" from the root project

Cause: Package requires a version range you're not using.

3. Duplicate Packages

warning "package-a" has unmet peer dependency "lodash@^4.0.0".
warning "package-b" has incorrect peer dependency "lodash@^3.0.0".

Cause: Multiple versions of the same package installed.

Diagnostic Commands

NPM

# See dependency tree
npm ls

# Find specific package
npm ls react

# Find why package is installed
npm why lodash

# Check for outdated packages
npm outdated

# Audit for issues
npm audit

Yarn

# See dependency tree
yarn list

# Find specific package
yarn why react

# Check for duplicates
yarn dedupe --check

# Interactive upgrade
yarn upgrade-interactive

PNPM

# See dependency tree
pnpm ls

# Find specific package
pnpm why react

# List all versions of a package
pnpm ls --depth Infinity | grep lodash

Resolution Strategies

Strategy 1: Update to Compatible Versions

# Find what versions are needed
npm ls react --all

# Update packages that need newer version
npm update package-a package-b

# Or install specific compatible version
npm install [email protected]

Strategy 2: Override/Resolution

NPM (package.json):

{
  "overrides": {
    "react": "18.2.0",
    "package-a": {
      "lodash": "4.17.21"
    }
  }
}