diff --git a/sponsorblockcast/Dockerfile b/sponsorblockcast/Dockerfile
index d76ea971a..feda99e2c 100644
--- a/sponsorblockcast/Dockerfile
+++ b/sponsorblockcast/Dockerfile
@@ -24,8 +24,8 @@ VOLUME [ "/data" ]
 
 # shellcheck ignore=DL4006
 RUN apk --no-cache add jq bc grep curl \
-    && GC_URL=`wget https://api.github.com/repos/vishen/go-chromecast/releases/latest -O - | jq -r '.assets[].browser_download_url' | grep ${TARGETOS}_${TARGETARCH}${TARGETVARIANT}` \
-    && wget "$GC_URL" -O /root/go-chromecast.tgz \
+    && GC_URL='wget https://api.github.com/repos/vishen/go-chromecast/releases/latest -O - | jq -r '.assets[].browser_download_url' | grep ${TARGETOS}_${TARGETARCH}${TARGETVARIANT}' \
+    && wget $GC_URL -O /root/go-chromecast.tgz \
     && tar xzf /root/go-chromecast.tgz -C /usr/bin \
     && rm -rf /root/* \
     && chmod +x /usr/bin/go-chromecast \