Answer by Danyil Suhak for How to include files outside of Docker's build context?

I only noticed that multiple build contexts were mentioned here when I decided to write the post.
Here is my service from docker-compose:

    frontend:        build:            context: ./frontend            additional_contexts:                - configs=./configs            dockerfile: Dockerfile

And here is my Dockerfile:

FROM node:18.16.1-alpine3.17 as builderRUN mkdir /frontendWORKDIR /frontendCOPY --from=configs ./.env.prod .

You can find more information about additional_contexts here:https://docs.docker.com/compose/compose-file/build/#additional_contexts

And there is information about Dockerfile and how build it with multiple context without docker-compose:https://www.docker.com/blog/dockerfiles-now-support-multiple-build-contexts/