diff --git a/kernel/Dockerfile b/kernel/Dockerfile
index c8ba2ee50..256f86e3b 100644
--- a/kernel/Dockerfile
+++ b/kernel/Dockerfile
@@ -84,6 +84,11 @@ RUN set -e && \
         done; \
     fi
 
+RUN mkdir -p /out/src
+
+# Save kernel source
+RUN tar cJf /out/src/linux.tar.xz /linux
+
 # Kernel config
 RUN case $(uname -m) in \
     x86_64) \
@@ -109,7 +114,6 @@ RUN case $(uname -m) in \
     make oldconfig && \
     if [ -z "${EXTRA}" ] && [ -z "${DEBUG}" ]; then diff .config ${KERNEL_DEF_CONF}; fi
 
-RUN mkdir /out
 
 # Kernel
 RUN make -j "$(getconf _NPROCESSORS_ONLN)" KCFLAGS="-fno-pie" && \
@@ -130,6 +134,7 @@ RUN make -j "$(getconf _NPROCESSORS_ONLN)" KCFLAGS="-fno-pie" && \
 # WireGuard
 RUN curl -sSL -o /wireguard.tar.xz "${WIREGUARD_URL}" && \
     echo "${WIREGUARD_SHA256}  /wireguard.tar.xz" | sha256sum -c - && \
+    cp /wireguard.tar.xz /out/src/ && \
     tar -C / --one-top-level=wireguard --strip-components=2 -xJf /wireguard.tar.xz "WireGuard-${WIREGUARD_VERSION}/src" && \
     make -j "$(getconf _NPROCESSORS_ONLN)" M="/wireguard" modules