Dev logs Docker layer caching and SQS priority queue lessons from KodeKloud tasks

A developer completing KodeKloud Engineer platform tasks documented two infrastructure lessons on day 47 of a learning series. For a Docker task packaging a Python app, they found that copying only the requirements file before running pip install — rather than copying the entire source directory first — prevents unnecessary dependency reinstalls when application code changes. On the AWS side, they built priority queues using SQS, SNS, and Lambda inside a CloudFormation template, but the first deployment rolled back due to an IAM permission error blocking inline role policies. Switching to managed policies resolved the failure, though it required granting broader permissions than the function strictly needed. The developer also noted that CloudFormation's validate-template command checks only syntax, not whether an account is actually authorized to perform the actions a template requests.