Example minimum Docker image for Buildkite Agent

Dockerfile

FROM alpine:3.4

RUN apk add --no-cache \
      tini \
      curl \
      wget \
      bash \
      git \
      perl \
      openssh-client

RUN mkdir -p \
      /usr/local/bin \
      /buildkite/builds \
      /buildkite/hooks \
      /buildkite/plugins \
    && wget -q \
         https://download.buildkite.com/agent/unstable/latest/buildkite-agent-linux-amd64 \
         -O /usr/local/bin/buildkite-agent \
    && chmod +x /usr/local/bin/buildkite-agent

ENV BUILDKITE_BUILD_PATH=/buildkite/builds \
    BUILDKITE_HOOKS_PATH=/buildkite/hooks \
    BUILDKITE_PLUGINS_PATH=/buildkite/plugins

ENTRYPOINT ["/sbin/tini", "-g", "--", "buildkite-agent"]

Instructions.bash

git clone https://gist.github.com/85b4c8b30c393d205203cedc341f8e73.git buildkite-agent-docker
cd buildkite-agent-docker
docker build -t buildkite-agent .
docker run -it --rm buildkite-agent start --token 'abc123'