prefer-aws-cdk-lib-offline-validation

Flags aws-cdk-lib versions below 2.262.0, which do not include the built-in offline CloudFormation validation.

Why it matters

• Before aws-cdk-lib 2.262.0, a CDK app could synthesize successfully and only fail later during deployment or provisioning.
• 2.262.0 began validating synthesized templates against default CloudFormation rules immediately after synthesis, so many misconfigurations fail before any deployment or change-set round trip.
• That validation runs automatically during cdk synth and cdk deploy, so enabling it does not require a separate step.
• Upgrade to 2.267.0 or later to also avoid the validator and performance-counter bugs present in 2.262.0-2.266.x.

Upgrading also picks up synthesis performance work released in the same period, such as faster file fingerprinting (2.254.0, about 30%) and a persisted fingerprint cache that speeds up re-synthesis (about 75%), which matter most for apps with large asset directories.

What it flags

• aws-cdk-lib below 2.262.0 in package.json.
• Versions at 2.262.0 or later are handled by prefer-aws-cdk-lib-2-267 or are already safe. The version is resolved from the committed lockfile when available, then from an exact pin in package.json. A caret range without a lockfile is treated as unknown and is not flagged.

Suggested action

• Upgrade aws-cdk-lib to 2.267.0 or later.

Verification

• Compare cdk synth and cdk deploy wall-clock time and failure feedback before and after the upgrade, and confirm validation runs right after synthesis.