For explaination follow my blog

https://github.com/ksingh7/laravel_custom_runtime_lambda.git

• Edit build.sh if you like to add a specific library to your Lambda Layer (optional)
• Edit regions.sh if you like to add multiple AWS regions to make your Lambda Layer available to
• Edit create-buckets.sh upload.sh publish.sh and unpublish.sh if you like to change the bucket name
• Edit php.ini if you like to enable PHP extentions of your choice (Make sure you have installed them using build.sh)

• Execute make to generate php71.zip in pwd. This is your Lambda Custom Layer file
• Execute create-buckets.sh to create bucket before uploading Lambda Layer to S3
• Execute upload.sh to upload Lambda Layer to S3
• Execute publish.sh to publish your custome Lambda Layer
• Optionally you can also make your Lambda Layer publicly available by editing necessary section from publish.sh
• Once Lambda layer is published to AWS Lambda, login to Lambda console > Layers and grab the Layer ARN
• Edit template.yaml and update Lambda Layer ARN

aws s3 mb s3://lambda-php-laravel-layer-us-east-1 \
    --region us-east-1 \
    --profile ksingh-lambda-v2

sam package \
    --template-file template.yaml \
    --output-template-file output/serverless-laravel.yaml \
    --s3-bucket lambda-php-laravel-layer-us-east-1 \
    --profile ksingh-lambda-v2 
   

sam deploy \
    --template-file output/serverless-laravel.yaml \
    --stack-name serverless-laravel \
    --capabilities CAPABILITY_IAM \
    --profile ksingh-lambda-v2

aws cloudformation delete-stack \
  --stack-name serverless-laravel \ 
  --profile ksingh-lambda-v2 

aws s3 rb --force s3://lambda-php-laravel-layer-us-east-1 \
  --profile ksingh-lambda-v2