diff --git a/Dockerfile b/Dockerfile
index 872340d..f40f679 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -23,9 +23,10 @@ RUN mix local.hex --force && mix local.rebar --force
 # Set build environment
 ENV MIX_ENV="prod"
 
-# Capture APRS parser git hash from GitHub API
-RUN curl -s https://api.github.com/repos/aprsme/aprs/commits/main | grep -o '"sha":"[^"]*"' | head -1 | cut -d'"' -f4 | cut -c1-7 > /tmp/parser_hash.txt
-ENV PARSER_GIT_HASH=$(cat /tmp/parser_hash.txt)
+# Capture APRS parser git hash from GitHub API and set as ENV
+RUN PARSER_GIT_HASH=$(curl -s https://api.github.com/repos/aprsme/aprs/commits/main | grep -o '"sha":"[^\"]*"' | head -1 | cut -d'"' -f4 | cut -c1-7) && \
+    echo "PARSER_GIT_HASH=$PARSER_GIT_HASH" > parser_git_hash.env
+ENV $(cat parser_git_hash.env | xargs)
 
 # Install dependencies
 COPY mix.exs mix.lock ./