diff --git a/Dockerfile b/Dockerfile
index cd90de7..4ede349 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,6 +3,7 @@ FROM public.ecr.aws/docker/library/ubuntu:24.04
 SHELL ["/bin/bash", "-o", "pipefail", "-c"]
 
 ENV DEBIAN_FRONTEND=noninteractive
+ARG MICROAGENT_TEST_AUTHORIZED_KEY=""
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
     ca-certificates \
@@ -37,7 +38,8 @@ RUN useradd --create-home --shell /bin/bash node \
   && chown -R node:node /home/node \
   && usermod -aG sudo node \
   && printf 'node ALL=(ALL) NOPASSWD:ALL\n' >/etc/sudoers.d/node \
-  && chmod 440 /etc/sudoers.d/node
+  && chmod 440 /etc/sudoers.d/node \
+  && install -d -m 0755 /etc/microagent
 
 COPY docker/guest/sshd_config /etc/ssh/sshd_config
 COPY docker/guest/microagent-init.sh /usr/local/bin/microagent-init
@@ -53,10 +55,16 @@ RUN chmod 755 /usr/local/bin/microagent-init /usr/local/bin/microagent-desktop-s
   && chown node:node /home/node/.zshrc /home/node/.bashrc /home/node/.profile \
   && usermod -s /usr/bin/zsh node \
   && install -d /opt/zsh/pure \
+  && ln -sf /usr/local/bin/microagent-init /sbin/init \
   && curl -fsSL https://raw.githubusercontent.com/sindresorhus/pure/v1.27.0/pure.zsh -o /opt/zsh/pure/pure.zsh \
   && curl -fsSL https://raw.githubusercontent.com/sindresorhus/pure/v1.27.0/async.zsh -o /opt/zsh/pure/async.zsh \
   && tic -x -o /usr/share/terminfo /tmp/xterm-ghostty.terminfo \
   && tic -x -o /usr/share/terminfo /tmp/xterm-kitty.terminfo \
   && rm -f /tmp/xterm-ghostty.terminfo /tmp/xterm-kitty.terminfo
 
+RUN if [ -n "$MICROAGENT_TEST_AUTHORIZED_KEY" ]; then \
+      printf '%s\n' "$MICROAGENT_TEST_AUTHORIZED_KEY" >/etc/microagent/authorized_keys; \
+      chmod 600 /etc/microagent/authorized_keys; \
+    fi
+
 CMD ["/usr/local/bin/microagent-init"]