Biggest pre:Invent 2024 serverless announcements

DynamoDB cuts on-demand price by 50%

Announcement

DynamoDB has reduced on-demand pricing by 50% and global tables by up to 67%. Amazing!

Lambda SnapStart is now available for Python and .Net

Announcement

Previously, SnapStart was only available for Java. It makes sense to add support for .Net. But why Python and not Node.js?

I guess SnapStart doesn’t do much for interpreted languages. But Python is used in many ML/AI workloads and SnapStart is useful when you need to load large AI models or ML libraries (such as NumPy).

This is why it can make sense for Python but not for Node.js.

Also, while SnapStart remains free to use for Java, it’s now a paid feature to use with Python and .Net. Check the Lambda pricing page for more details.

Lambda supports Node.js 22

Announcement

Aurora Serverless v2 supports scaling-to-zero

Announcement

Aurora Serverless v2 can now auto-pause after a period of inactivity. But it now also has a 15-25s cold start when it resumes from pause.

This is mainly useful for non-production environments. You can save some cost by letting the cluster scale to zero when no one is using it.

However, there are many situations when auto-pause is not possible. Check out the “Situations where Aurora Serverless v2 doesn’t auto-pause” section here.

CloudFront functions now support dynamic routing

Announcement

You can now use CloudFront functions to dynamically route a request to a different origin or create a new origin on request. Previously, this was only possible through Lambda@Edge.

CloudFront functions are much faster to deploy than Lambda@Edge. Its logs are always streamed to us-east-1, whereas Lambda@Edge logs are streamed to the region where the function was executed, which makes them a nightmare to find and collect!

The less we need to use Lambda@Edge, the better.

Cognito has a complete overhaul. New features, better customizable UI, new pricing tiers

Announcement

Blog post on new features

So much to unpack here.

The new Managed Login feature is a big upgrade on the previous Hosted UI feature. It allows much more customization and branding on the hosted login page.

The new Passwordless Login support reduces the need for custom auth flows ?like this?. Passwordless authentication with passkeys and one-time passwords can now be enabled with a setting.

Price tiers

There are now three price tiers:

• Lite – existing Cognito User Pool features. Advanced Security Features (e.g. access token customization) are charged on top of the base price, as before.
• Essentials – new features like the Managed Login and Passwordless Login mentioned above.
• Plus – geared towards enterprise users and includes features such as adaptive authentication and compromised credentials detection.

The free tier has been reduced from 50k MAU to 10k MAU.

You can upgrade your existing user pools (that don’t use Advanced Security Features) to the Essentials tier and pay the previous price until Nov 30, 2025.

Step Functions simplifies data manipulation with JSONata and variables

Announcement

Step Functions had a big problem with data flows – it had five different attributes to manipulate input and output with JSONPath:

• InputPath
• Parameters
• ResultPath
• ResultSelector
• OutputPath

Plus, we often had to use Pass states to manipulate data between one state and another.

Now, you can use JSONATA to query and transform variables that you can read and write throughout the state machine. This drastically simplifies data flows in Step Functions.

However, for complex workflows, I think Restate will still be significantly simpler. Check out the demo in the latest episode of Real-World Serverless.

Lambda supports S3 as a failure destination

Announcement

This can be useful if you want to have a more permanent storage for failed events. It also makes analyzing and reprocessing failed events easier. You can even use Athena to query the failed events and use it to make a case-by-case decision on what to reprocess.

New metrics for Lambda Event-Source Mappings (ESMs)

Announcement

Lambda has added a number of new metrics for ESMs, including:

• PolledEventCount
• InvokedEventCount
• FailedInvokeEventCount

and more. The new metrics make it easier to identify problems with processing events. At launch, only SQS, DynamoDB Streams and Kinesis Streams support these new metrics.

I did a deeper dive into these new metrics and when to use them. For more details, check out this post.

CloudWatch Log Insights can query “all log groups”

Announcement

CloudWatch Logs Insights no longer limits you to just 20 log groups (which was a silly limitation anyway).

CloudFormation Hooks let you perform validation on template

Announcement

This is another way for you to run validation logic (using Lambda functions) against a CloudFormation template.

You can choose when the hooks run, based on resource type, name, deployment action, stack name, etc.

But wait, there are other ways to perform validation on CloudFormation templates already, including:

• AWS Config
• Client-side tools such as cdk-nag/cfn_nag/etc.

The difference is:

• vs. AWS Config: AWS Config kicks in AFTER the deployment. CloudFormation Hooks can be executed before a resource is provisioned.
• vs. Client-side tools: The question is who owns the validation logic. It’s difficult to enforce client-side tools across a large organization. It’s easier for platform teams to ensure compliance by installing their hooks in each AWS account they provision.

Predictive scaling for ECS

Announcement

Predictive scaling is great for ECS, but it’s gonna be HUGE when they bring it to Lambda.

Just imagine not having to deal with cold starts because the platform proactively initializes new workers ahead of time.

AppSync simplifies cross-account API access with Resource Access Manager (RAM)

Announcement

ALB support inserting, deleting and modifying headers

Announcement

This makes it easier to manage security headers like HSTS or CORS. You can manage them centrally at the ALB level, reducing the need for application-level changes and hopefully reducing the risk of configuration errors as well.