I really don't struggle that much with cold starts on Node.js/Lambda, and I don't do anything special, my build commands look like:

    esbuild src/handler.ts --bundle --external:@aws-lambda-powertools --external:@aws-sdk --minify --outfile=dist/handler.js --platform=node --sourcemap --target=es2022 --tree-shaking=true

Maybe I'm not doing as much as others in my functions and I tend to stick within the AWS ecosystem, so I save some space and I presume cold-start time by not including the AWS SDK/Powertools in the output, but my functions tend to cold start and complete in ~100ms.