Posts by Yan Cui

Yan Cui is an AWS Serverless Hero and Lumigo Developer Advocate. He is the author of Production-Ready Serverless.

Serverless Observability: Lumigo or AWS X-Ray
Observability is a measure of how well we are able to infer the internal state of our application from its...
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Lessons Learned From Running Serverless In Production For 5 Years
I have been an AWS customer since 2010 and in the early days I, along with just about everyone else...
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Testing strategies for Step Functions
AWS Step Functions is a powerful orchestration service that lets you model even the most complex business workflows. It packs...
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Lambda Extensions Just Got Even Better
AWS announced AWS Lambda Extensions back in October 2020 and I wrote extensively about it at the time - what...
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3 Major Ways To Improve AWS Lambda Performance
When it comes to performance, AWS Lambda gives you a single configuration to control the performance and cost of your...
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Amazon Builders' Library in Focus #6: Implementing Health Checks
In our latest article on the Amazon Builders’ Library, Yan Cui highlights the main takeaways from the article, Implementing health...
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Amazon Builders' Library in focus #5: Static stability using availability zones
Next in our series on the Amazon Builders’ Library, Yan Cui picks out the key insights from the article, Static...
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Amazon Builders' Library in focus #4: Avoiding insurmountable queue backlogs
In the latest article in our series focusing on the Amazon Builders’ Library, Yan Cui highlights the key insights from...
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Amazon Builders’ Library in focus #3: Avoiding fallback in distributed systems
In the third of our series of articles, Yan Cui highlights the key insights from the Amazon Builders’ Library article,...
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Amazon Builders’ Library in focus #2: Using load shedding to avoid overload
In the second of our new series of posts, Yan Cui highlights the key insights from the Amazon Builders’ Library...
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Amazon Builders’ Library in focus #1: Timeouts, retries, and backoff with jitter
In the first article in our new series, Yan Cui highlights the key insights from the Amazon Builders’ Library article,...
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AWS Lambda Provisioned Concurrency: The End of Cold Starts
What Is Provisioned Concurrency? Amazon Lambda is a serverless runtime that offers provisioned concurrency, which is a feature that extends...
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The why, when and how of AWS API Gateway service proxies
Serverless Hero Yan Cui explains when and why you should use AWS API Gateway service proxies, and introduces an open...
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Monitor Lambda cold start durations with CloudWatch
When you look at an X-Ray trace for a Lambda cold start, you will see an Initialization subsegment. This subsegment...
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Introducing the lumigo-cli
Here at Lumigo, we are big fans of serverless. And a big part of working with AWS Lambda involves using...
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Top 10 best practices for serverless.yml
The Serverless Framework is one of the oldest (and still going strong!) deployment frameworks around for serverless applications. It’s my...
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The best reason to use AWS DynamoDB streams
Many clients have asked me, “When do I use AWS DynamoDB streams vs Kinesis?” It’s a great question, since both...
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A SAR app to propagate CloudFormation tags to unsupported resources
Did you know that CloudFormation tags don't automatically propagate to some resource types? Chief among these are CloudWatch log groups,...
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Serverless Framework Plugin: Get Instant Visibility
Observability is a common challenge for serverless applications and we believe Lumigo is perfectly positioned to help you tackle this...
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SQS and Lambda: a Quick Tutorial and How to Handle Failure Modes
How do SQS and Lambda Work Together? Amazon SQS is a lightweight, fully-managed message queueing service. You can use SQS...
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CloudWatch Logs for AWS Lambda: Getting Insights About Your Serverless Deployment
AWS CloudWatch is a powerful tool, but it can be tricky to use it for monitoring your AWS Lambda functions....
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Amazon EventBridge: a new era of SaaS integration
Amazon recently announced EventBridge to much fanfare. Although, in truth, it’s a rebranding of the existing CloudWatch Events service, along...
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Serverless app to speed up all your Lambda functions
A while back, I wrote about how you can shave latency off every AWS SDK operation by enabling HTTP keep-alive,...
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Lambda and Kinesis - beware of hot streams
Back in 2017, I wrote a post titled “3 pro tips for Developers working with Kinesis streams”, in which I...
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You are wrong about serverless vendor lock-in
Some time ago, the Register published an article titled “Lambda and serverless is one of the worst forms of proprietary...
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Mono-repo vs one-per-service
With AWS Lambda, we can deploy and scale individual functions. However, we engineers still like to think in terms of...
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Canary Deployment with LaunchDarkly and AWS Lambda
LaunchDarkly has built an impressive feature flag management system that overages more than 200 billion feature flags per day. It...
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AWS Lambda Use Cases: When to use Lambda layers
AWS introduced Lambda Layers at re:invent 2018 as a way to share code and data between functions within and across...
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AWS Lambda apps to automate chores around CloudWatch Logs
The open source applications described in this article are available from Lumigo's Github repository. If you look around the Serverless...
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An AWS Lambda app to clean up old deployment packages
AWS Lambda has a soft limit of 75GB for deployment packages for all your functions (including the layers you use)....
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