docker Dockerfile FROM can appear multiple times

FROM alpine:latest
RUN apk --update add ca-certificates
FROM scratch

FROM can appear multiple times within a singleDockerfileto create multiple images or use one build stage as a dependency for another. Simply make a note of the last image ID output by the commit before each new FROM instruction. Each FROM instruction clears any state created by previous instructions.

https://docs.docker.com/engine/reference/builder/