diff --git a/mastodon/Dockerfile.master b/mastodon/Dockerfile.master
index a167a98..994afea 100644
--- a/mastodon/Dockerfile.master
+++ b/mastodon/Dockerfile.master
@@ -56,8 +56,8 @@ RUN apk -U upgrade \
 
 # Install GNU Libiconv
  && wget http://ftp.gnu.org/pub/gnu/libiconv/libiconv-${LIBICONV_VERSION}.tar.gz -O /tmp/libiconv-${LIBICONV_VERSION}.tar.gz \
- && tar xzf /tmp/libiconv-${LIBICONV_VERSION}.tar.gz -C /usr/src \
- && cd /usr/src/libiconv-${LIBICONV_VERSION} \
+ && mkdir /tmp/src && tar xzf /tmp/libiconv-${LIBICONV_VERSION}.tar.gz -C /tmp/src \
+ && cd /tmp/src/libiconv-${LIBICONV_VERSION} \
  && ./configure --prefix=/usr/local \
  && make && make install && libtool --finish /usr/local/lib \
 
diff --git a/mastodon/Dockerfile.stable b/mastodon/Dockerfile.stable
index bcea6bc..f156457 100644
--- a/mastodon/Dockerfile.stable
+++ b/mastodon/Dockerfile.stable
@@ -1,6 +1,6 @@
 FROM alpine:3.6
 
-ARG VERSION=v1.5.0
+ARG VERSION=v1.5.1
 ARG REPOSITORY=tootsuite/mastodon
 ARG LIBICONV_VERSION=1.15
 
@@ -56,8 +56,8 @@ RUN apk -U upgrade \
 
 # Install GNU Libiconv
  && wget http://ftp.gnu.org/pub/gnu/libiconv/libiconv-${LIBICONV_VERSION}.tar.gz -O /tmp/libiconv-${LIBICONV_VERSION}.tar.gz \
- && tar xzf /tmp/libiconv-${LIBICONV_VERSION}.tar.gz -C /usr/src \
- && cd /usr/src/libiconv-${LIBICONV_VERSION} \
+ && mkdir /tmp/src && tar xzf /tmp/libiconv-${LIBICONV_VERSION}.tar.gz -C /tmp/src \
+ && cd /tmp/src/libiconv-${LIBICONV_VERSION} \
  && ./configure --prefix=/usr/local \
  && make && make install && libtool --finish /usr/local/lib \
 
diff --git a/mastodon/Dockerfile.targaryen b/mastodon/Dockerfile.targaryen
index 70f1c50..4216b90 100644
--- a/mastodon/Dockerfile.targaryen
+++ b/mastodon/Dockerfile.targaryen
@@ -1,6 +1,6 @@
-FROM alpine:3.6
+FROM alpine:edge
 
-ARG VERSION=v1.5.0
+ARG VERSION=v1.5.1
 ARG REPOSITORY=tootsuite/mastodon
 ARG LIBICONV_VERSION=1.15
 
@@ -77,7 +77,7 @@ RUN apk -U upgrade \
  && mv public/assets /tmp/assets && mv public/packs /tmp/packs \
 
 # Clean
- && npm -g cache clean && yarn cache clean \
+ && npm -g cache clean --force && yarn cache clean \
  && apk del build-dependencies \
  && rm -rf /var/cache/apk/* /tmp/src