Hi there

you need to add `libyaml-dev` to your Dockerfile in the build phase

# Throw-away build stage to reduce size of final image
FROM base as build

# Install packages needed to build gems and node modules
ARG BUILD_PACKAGES="git build-essential libpq-dev wget curl gzip libyaml-dev"
ENV BUILD_PACKAGES ${BUILD_PACKAGES}

RUN apt-get update -qq && \
    apt-get install --no-install-recommends -y ${BUILD_PACKAGES} \
    && rm -rf /var/lib/apt/lists /var/cache/apt/archives

if you don't have a Dockerfile, you create a new one by adding this gem to your Gemfile

gem "dockerfile-rails", ">= 1.7", group: :development

then

and to generate a Dockerfile along with relevant files

rails g dockerfile

this will read your app structure and create a Dockerfile for all your dependencies, you might need to discard some of the changes or delete some of the files depending on your setup.

commit push and it should all work now!

let me know how it goes and if you found this answer to be helpful feel free to mark is as accepted!

thanks

alex