diff --git a/2.2/jessie/slim/Dockerfile b/2.2/jessie/slim/Dockerfile
index 65d9fd3c4..2cbf0aba3 100644
--- a/2.2/jessie/slim/Dockerfile
+++ b/2.2/jessie/slim/Dockerfile
@@ -76,6 +76,9 @@ RUN set -ex \
 	&& make -j "$(nproc)" \
 	&& make install \
 	\
+	&& dpkg-query --show --showformat '${package}\n' \
+		| grep -P '^libreadline\d+$' \
+		| xargs apt-mark manual \
 	&& apt-get purge -y --auto-remove $buildDeps \
 	&& cd / \
 	&& rm -r /usr/src/ruby \
diff --git a/2.3/jessie/slim/Dockerfile b/2.3/jessie/slim/Dockerfile
index 362c276ba..fadd38c10 100644
--- a/2.3/jessie/slim/Dockerfile
+++ b/2.3/jessie/slim/Dockerfile
@@ -76,6 +76,9 @@ RUN set -ex \
 	&& make -j "$(nproc)" \
 	&& make install \
 	\
+	&& dpkg-query --show --showformat '${package}\n' \
+		| grep -P '^libreadline\d+$' \
+		| xargs apt-mark manual \
 	&& apt-get purge -y --auto-remove $buildDeps \
 	&& cd / \
 	&& rm -r /usr/src/ruby \
diff --git a/2.4/jessie/slim/Dockerfile b/2.4/jessie/slim/Dockerfile
index c9ef21101..815d33acb 100644
--- a/2.4/jessie/slim/Dockerfile
+++ b/2.4/jessie/slim/Dockerfile
@@ -76,6 +76,9 @@ RUN set -ex \
 	&& make -j "$(nproc)" \
 	&& make install \
 	\
+	&& dpkg-query --show --showformat '${package}\n' \
+		| grep -P '^libreadline\d+$' \
+		| xargs apt-mark manual \
 	&& apt-get purge -y --auto-remove $buildDeps \
 	&& cd / \
 	&& rm -r /usr/src/ruby \
diff --git a/2.4/stretch/slim/Dockerfile b/2.4/stretch/slim/Dockerfile
index e5286d33d..908442235 100644
--- a/2.4/stretch/slim/Dockerfile
+++ b/2.4/stretch/slim/Dockerfile
@@ -76,6 +76,9 @@ RUN set -ex \
 	&& make -j "$(nproc)" \
 	&& make install \
 	\
+	&& dpkg-query --show --showformat '${package}\n' \
+		| grep -P '^libreadline\d+$' \
+		| xargs apt-mark manual \
 	&& apt-get purge -y --auto-remove $buildDeps \
 	&& cd / \
 	&& rm -r /usr/src/ruby \
diff --git a/Dockerfile-slim.template b/Dockerfile-slim.template
index 3f3249182..79b68cb41 100644
--- a/Dockerfile-slim.template
+++ b/Dockerfile-slim.template
@@ -76,6 +76,9 @@ RUN set -ex \
 	&& make -j "$(nproc)" \
 	&& make install \
 	\
+	&& dpkg-query --show --showformat '${package}\n' \
+		| grep -P '^libreadline\d+$' \
+		| xargs apt-mark manual \
 	&& apt-get purge -y --auto-remove $buildDeps \
 	&& cd / \
 	&& rm -r /usr/src/ruby \