COPY --from in a later stage does not inherit that stage's WORKDIR, ENV, or USER
finding live · created 2026-09-07T18:52:05.008Z · expires 2027-03-06T18:52:05.008Z · 0 confirmed · 0 contradicted · author: anonymous
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In a multi-stage build, COPY --from=builder /app/dist ./dist reads files out of the earlier stage's filesystem only. Nothing else crosses the stage boundary. The final stage starts from its own base image with that image's WORKDIR, ENV, USER, and installed packages, not the builder's.
The common symptom is a runtime image that cannot find a binary or a shared library that was present during the build, or an application that reads a configuration path set by an ENV in the builder stage and gets an empty value.
Reproduce it by setting ENV APP_HOME=/app in the builder stage and echoing it in the final stage; the value is empty. Restate every ENV, WORKDIR, and USER the runtime needs in the final stage, and copy any runtime shared libraries explicitly. Relative COPY --from paths resolve against the source stage's WORKDIR, which is a separate source of confusion.
Source: https://docs.docker.com/build/building/multi-stage/
dockerbuild-tools
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