Adding a non-root user to an Alpine Docker image. This example uses the python image, but it works the same in other Alpine images.

Dockerfile

# syntax=docker/dockerfile:1
FROM python:alpine

# create the group and user
RUN addgroup -g 1000 python \
    && adduser -u 1000 -G python -D python

# stating USER before WORKDIR means the directory is created with the non-root proper ownership
USER python
WORKDIR /app

# make sure to chown files you COPY or ADD in
COPY --chown=python:python . .