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Roger Chi

@rogerchi.com

Engineering, VP @ ITE Management | AWS Community Builder - Serverless

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19.09.2023
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Latest posts by Roger Chi @rogerchi.com

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AppSync Cache Eviction with Lambda Data Sources AppSync is a fully managed, serverless GraphQL API service from AWS. It has the concept of data...

How do you evict entries in AppSync's cache if you're using a Lambda Datasource? Here's an article that explains how:

AppSync Cache Eviction with Lambda Data Sources #DEVCommunity #appsync #serverless #aws dev.to/aws-builders...

01.02.2026 02:51 πŸ‘ 0 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
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Simple Service Relationships in EventBridge Event-driven architectures are powerful. Services communicate through events, staying loosely coupled...

I wrote an article describing a simple strategy for discovering service relationships in an EventBridge-based event-driven system. dev.to/aws-builders... #DEVCommunity #awscdk #eventbridge

12.01.2026 14:06 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
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AWS AppConfig multi-accounts, multi-environments with ease AppConfig is AWS's native solution for feature flagging and dynamic configuration management. It...

I wrote up my experiences setting up AWS AppConfig as a feature flagging tool, coming from having used tools like LaunchDarkly and Statsig in the past. dev.to/rogerchi/aws... #aws #serverless #appconfig

30.01.2025 19:28 πŸ‘ 3 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

Not based on my testing β€” with a 1kb item I was only able to achieve 167 RPS. Of course optimistic locking is more cost efficient because it only requires one write, but there are many situations where pessimistic locking is required.

10.12.2024 17:05 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

The choice between optimistic locking and pessimistic locking depends on the cost of retrying and chance for conflict. My article is specifically about when you want to use pessimistic locking. There is a larger throughput penalty for DDB transactions as you cannot achieve the full RPS as expected.

10.12.2024 14:32 πŸ‘ 0 πŸ” 0 πŸ’¬ 2 πŸ“Œ 0
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A Mental Model for DynamoDB Write Limits Amazon's DynamoDB is promoted as a zero-maintenance, virtually unlimited throughput and scale* NoSQL...

A simple scenario is a user opens an item for modification. You don’t want the item to change out from under them, so you need some form of locking. Transactions don’t really do anything for you here. Plus there is a large throughput penalty for using transactions: dev.to/aws-builders...

10.12.2024 14:14 πŸ‘ 2 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
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Practical DynamoDB - Locking Reads Amazon's DynamoDB is promoted as a zero-maintenance, virtually unlimited throughput and scale* NoSQL...

I wrote an article about a useful pattern for pessimistic locking in #dynamodb dev.to/aws-builders... #aws #serverless

05.12.2024 17:00 πŸ‘ 11 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
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GitHub - CloudSnorkel/cdk-github-runners: CDK constructs for self-hosted GitHub Actions runners CDK constructs for self-hosted GitHub Actions runners - CloudSnorkel/cdk-github-runners

I used this to spin them up recently and it was very easy github.com/CloudSnorkel...

01.12.2024 14:20 πŸ‘ 3 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

Fairly sure you pay the same cost (twice the WCU per item for all items in the transaction) whether the transaction succeeds or fails. Returning the item attributes due to a condition check failure doesn’t cost anything extra. You can also specify ReturnConsumedCapacity to get the exact costs.

22.11.2024 13:39 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

I saw some neat things that haven’t been announced yet show up in the CloudWatch console

21.11.2024 23:24 πŸ‘ 2 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0