Configuration precision matters

Ensure configuration files are precise and stable to prevent unexpected build failures and runtime issues. This includes:

1. Use correct syntax in configuration files Validate JSON files for syntax errors like extra commas, which can cause cryptic error messages during builds.

   // Incorrect
   {
     "$schema": "https://turborepo.com/schema.json",,
     "ui": "tui"
   }
      
   // Correct
   {
     "$schema": "https://turborepo.com/schema.json",
     "ui": "tui"
   }
   

2. Specify exact versions for critical dependencies Use exact versions instead of ranges (^ or ~) for dependencies when stability is critical, especially in test fixtures or shared packages.

   // Less stable (allows minor updates)
   "dependencies": {
     "@types/d3-scale": "^4.0.2"
   }
      
   // More stable (locks exact version)
   "dependencies": {
     "@types/d3-scale": "4.0.2"
   }
   

3. Explicitly specify package manager Include the packageManager field in package.json to ensure consistent behavior across environments, especially when using version wildcards (*).

   {
     "name": "monorepo",
     "packageManager": "pnpm@8.14.0",
     "dependencies": {
       "util": "*"
     }
   }
   

4. Establish clear sources of truth Define which configuration files are authoritative for specific settings. For example, make package.json’s engines field the definitive source for Node.js version requirements.

   "engines": {
     "node": "22.x"
   }
   

These practices reduce configuration drift, prevent unexpected behavior, and help maintain consistency across environments and team members.