Version Constraints

Composer uses semantic versioning. Constraint operators control which updates are allowed.

Example

"require": {
  "vendor/pkg": "1.2.3",      // exact
  "vendor/pkg": ">=1.2 <2.0", // range
  "vendor/pkg": "^1.2",       // >=1.2.0 <2.0.0 (semver safe)
  "vendor/pkg": "~1.2",       // >=1.2.0 <1.3.0 (patch only)
  "vendor/pkg": "*",           // any (dangerous)
  "vendor/pkg": "dev-main"    // git branch
}

JSON

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Pro Tip

Prefer ^ (caret) constraints — they allow minor and patch updates but block major breaking changes.

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