It will depend heavily on the docker image you're trying to ship. For example with macos-cross-compiler[0] the resulting binary is over 2GB. With python:alpine[1] it's only 25MB.

Because the image isn't copied whether the image is 2GB or 25MB the startup time will be nearly instantaneous for both.

The runtime adds 6-7MB of overhead although I expect that this can be reduced to less than 3MB with some work.

[0]: https://github.com/shepherdjerred/macos-cross-compiler [1]: https://hub.docker.com/_/python