diff --git a/3.2/32bit/Dockerfile b/3.2/32bit/Dockerfile
index fa663724..59e85536 100644
--- a/3.2/32bit/Dockerfile
+++ b/3.2/32bit/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:jessie-slim
+FROM debian:stretch-slim
 
 # add our user and group first to make sure their IDs get assigned consistently, regardless of whatever dependencies get added
 RUN groupadd -r redis && useradd -r -g redis redis
@@ -8,7 +8,12 @@ RUN groupadd -r redis && useradd -r -g redis redis
 ENV GOSU_VERSION 1.10
 RUN set -ex; \
 	\
-	fetchDeps='ca-certificates wget'; \
+	fetchDeps=" \
+		ca-certificates \
+		dirmngr \
+		gnupg \
+		wget \
+	"; \
 	apt-get update; \
 	apt-get install -y --no-install-recommends $fetchDeps; \
 	rm -rf /var/lib/apt/lists/*; \
@@ -19,6 +24,7 @@ RUN set -ex; \
 	export GNUPGHOME="$(mktemp -d)"; \
 	gpg --keyserver ha.pool.sks-keyservers.net --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
 	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
+	gpgconf --kill all; \
 	rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc; \
 	chmod +x /usr/local/bin/gosu; \
 	gosu nobody true; \
diff --git a/3.2/Dockerfile b/3.2/Dockerfile
index 8c1b30a3..8b86eb41 100644
--- a/3.2/Dockerfile
+++ b/3.2/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:jessie-slim
+FROM debian:stretch-slim
 
 # add our user and group first to make sure their IDs get assigned consistently, regardless of whatever dependencies get added
 RUN groupadd -r redis && useradd -r -g redis redis
@@ -8,7 +8,12 @@ RUN groupadd -r redis && useradd -r -g redis redis
 ENV GOSU_VERSION 1.10
 RUN set -ex; \
 	\
-	fetchDeps='ca-certificates wget'; \
+	fetchDeps=" \
+		ca-certificates \
+		dirmngr \
+		gnupg \
+		wget \
+	"; \
 	apt-get update; \
 	apt-get install -y --no-install-recommends $fetchDeps; \
 	rm -rf /var/lib/apt/lists/*; \
@@ -19,6 +24,7 @@ RUN set -ex; \
 	export GNUPGHOME="$(mktemp -d)"; \
 	gpg --keyserver ha.pool.sks-keyservers.net --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
 	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
+	gpgconf --kill all; \
 	rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc; \
 	chmod +x /usr/local/bin/gosu; \
 	gosu nobody true; \
diff --git a/4.0/32bit/Dockerfile b/4.0/32bit/Dockerfile
index dbae92d3..9d6e3fe8 100644
--- a/4.0/32bit/Dockerfile
+++ b/4.0/32bit/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:jessie-slim
+FROM debian:stretch-slim
 
 # add our user and group first to make sure their IDs get assigned consistently, regardless of whatever dependencies get added
 RUN groupadd -r redis && useradd -r -g redis redis
@@ -8,7 +8,12 @@ RUN groupadd -r redis && useradd -r -g redis redis
 ENV GOSU_VERSION 1.10
 RUN set -ex; \
 	\
-	fetchDeps='ca-certificates wget'; \
+	fetchDeps=" \
+		ca-certificates \
+		dirmngr \
+		gnupg \
+		wget \
+	"; \
 	apt-get update; \
 	apt-get install -y --no-install-recommends $fetchDeps; \
 	rm -rf /var/lib/apt/lists/*; \
@@ -19,6 +24,7 @@ RUN set -ex; \
 	export GNUPGHOME="$(mktemp -d)"; \
 	gpg --keyserver ha.pool.sks-keyservers.net --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
 	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
+	gpgconf --kill all; \
 	rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc; \
 	chmod +x /usr/local/bin/gosu; \
 	gosu nobody true; \
diff --git a/4.0/Dockerfile b/4.0/Dockerfile
index b0ad0555..2572224e 100644
--- a/4.0/Dockerfile
+++ b/4.0/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:jessie-slim
+FROM debian:stretch-slim
 
 # add our user and group first to make sure their IDs get assigned consistently, regardless of whatever dependencies get added
 RUN groupadd -r redis && useradd -r -g redis redis
@@ -8,7 +8,12 @@ RUN groupadd -r redis && useradd -r -g redis redis
 ENV GOSU_VERSION 1.10
 RUN set -ex; \
 	\
-	fetchDeps='ca-certificates wget'; \
+	fetchDeps=" \
+		ca-certificates \
+		dirmngr \
+		gnupg \
+		wget \
+	"; \
 	apt-get update; \
 	apt-get install -y --no-install-recommends $fetchDeps; \
 	rm -rf /var/lib/apt/lists/*; \
@@ -19,6 +24,7 @@ RUN set -ex; \
 	export GNUPGHOME="$(mktemp -d)"; \
 	gpg --keyserver ha.pool.sks-keyservers.net --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
 	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
+	gpgconf --kill all; \
 	rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc; \
 	chmod +x /usr/local/bin/gosu; \
 	gosu nobody true; \