drissamri/aws-lambda-starter-java11

aws-lambda-starter-java11

Architecture Decision Record (ADR):

• Leverage AWS Lambda startup CPU boost: initialize everything in static blocks & constructor

• Leverage AWS Lambda startup unbilled time:

  • Do mock DynamoDB GET to initialize marshallers in constructor

• Minimize dependencies used & prefer lightweight alternatives

  • Use url-connection-client and exclude apache-client & netty-nio-client
  • No dependency injection unless too many classes

• Symphonia logging (logback) over Log4j2: faster startup (~300ms) & smaller (-1 MB)

• Leverage Enhanced DynamoDB client to minimize boilerplate and almost no cold start penalty

  • https://aws.amazon.com/blogs/developer/introducing-enhanced-dynamodb-client-in-the-aws-sdk-for-java-v2/

• Configure as much as possible on DynamoDB (region, credentials lookup, http client) to minimize lookup delay

  • https://docs.aws.amazon.com/sdk-for-java/v2/developer-guide/client-configuration-starttime.html

• Use ZIP deployment over uber/shaded-jar