remotion-dev/remotion · warning · Error

AWS did not return a runtime version ARN.

Error message

AWS did not return a runtime version ARN.

What it means

After creating a function, createFunction() pins the Node runtime by calling PutRuntimeManagementConfig with a RuntimeVersionArn. For the aws-cn partition it uses the ARN returned by GetFunction; when AWS never returned one (RuntimeVersionConfig absent while state left 'Pending'), this error is thrown. Importantly, the throw sits inside a try/catch that downgrades it to a console.warn - function creation still succeeds; only runtime locking is skipped.

Source

Thrown at packages/lambda/src/api/create-function.ts:342

	RenderInternals.Log.verbose(
		{indent: false, logLevel},
		'Function is now ready.',
	);

	RenderInternals.Log.verbose(
		{indent: false, logLevel},
		'Locking the runtime version of the function...',
	);

	const runtimeVersionArn =
		partition === 'aws-cn'
			? currentRuntimeVersionArn
			: `arn:aws:lambda:${region}::runtime:58a37e8413ed69058c4ac3b1df642118591f17d40def93d6101f867c72cd03c2`;

	try {
		if (!runtimeVersionArn) {
			throw new Error('AWS did not return a runtime version ARN.');
		}

		await LambdaClientInternals.getLambdaClient(
			region,
			undefined,
			requestHandler,
		).send(
			new PutRuntimeManagementConfigCommand({
				FunctionName,
				UpdateRuntimeOn: 'Manual',
				RuntimeVersionArn: runtimeVersionArn,
			}),
		);

		RenderInternals.Log.verbose(
			{indent: false, logLevel},
			`Function runtime is locked to ${runtimeVersionArn}`,
		);

View on GitHub (pinned to 10db9de073)

Solutions

1. Treat it as non-fatal - the function was created; only runtime version locking was skipped (you saw the 'Could not lock the runtime version' warning)
2. Update @remotion/lambda to the latest version, which tracks current AWS behavior
3. Ensure the deploy role allows lambda:GetFunction so RuntimeVersionConfig is returned
4. Optionally pin the runtime manually in the AWS console (Runtime settings -> Update runtime on: Manual) if you need deterministic runtimes

When it happens

Trigger: Deploying a Remotion Lambda function in an aws-cn (China) partition region where GetFunction's Configuration.RuntimeVersionConfig.RuntimeVersionArn stays null, or where the AWS response lacks the runtime version field entirely (packages/lambda/src/api/create-function.ts:335-365).

Common situations: China-partition deployments where the runtime-version API surface differs from the global partition; older @remotion/lambda versions against changed AWS responses; IAM policies missing lambda:GetFunction details. End result is only the warning 'Could not lock the runtime version'.

Related errors

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• Render did not finish yet
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• maxRetries must be finite, but is ${maxRetries}
• parameter 'vpcSecurityGroupIds' must either be 'undefined' o

AI-assisted analysis of remotion-dev/remotion@10db9de073 (2026-08-22). Data as JSON: /api/errors/cdd6eb6df7e7d2c8. Report an issue: GitHub.