gistfile1.txt

diff --git a/8.4/Dockerfile b/8.4/Dockerfile
index 95e7a64..6b3139d 100644
--- a/8.4/Dockerfile
+++ b/8.4/Dockerfile
@@ -9,13 +9,13 @@ RUN apt-get update && \
     echo 'deb http://downloads.haskell.org/debian stretch main' > /etc/apt/sources.list.d/ghc.list && \
     apt-key adv --keyserver keyserver.ubuntu.com --recv-keys BA3CBA3FFE22B574 && \
     apt-get update && \
-    apt-get install -y --no-install-recommends ghc-8.4.3 cabal-install-2.2 \
+    apt-get install -y --no-install-recommends ghc cabal-install \
         zlib1g-dev libtinfo-dev libsqlite3-dev g++ netbase xz-utils make && \
-    curl -fSL https://github.com/commercialhaskell/stack/releases/download/v1.7.1/stack-1.7.1-linux-x86_64.tar.gz -o stack.tar.gz && \
-    curl -fSL https://github.com/commercialhaskell/stack/releases/download/v1.7.1/stack-1.7.1-linux-x86_64.tar.gz.asc -o stack.tar.gz.asc && \
+    curl -fSL https://github.com/commercialhaskell/stack/releases/download/v1.7.1/stack-1.7.1-linux-aarch64.tar.gz -o stack.tar.gz && \
+    curl -fSL https://github.com/commercialhaskell/stack/releases/download/v1.7.1/stack-1.7.1-linux-aarch64.tar.gz.asc -o stack.tar.gz.asc && \
     apt-get purge -y --auto-remove curl && \
     export GNUPGHOME="$(mktemp -d)" && \
-    gpg --keyserver ha.pool.sks-keyservers.net --recv-keys C5705533DA4F78D8664B5DC0575159689BEFB442 && \
+    gpg --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys C5705533DA4F78D8664B5DC0575159689BEFB442 && \
     gpg --batch --verify stack.tar.gz.asc stack.tar.gz && \
     tar -xf stack.tar.gz -C /usr/local/bin --strip-components=1 && \
     /usr/local/bin/stack config set system-ghc --global true && \