diff --git a/Dockerfile b/Dockerfile
index 4cdcd40e8..bf5831832 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -14,8 +14,6 @@ WORKDIR /src
 ARG TARGETOS
 ARG TARGETARCH
 ARG FLAGS
-ENV GOOS $TARGETOS
-ENV GOARCH $TARGETARCH
 RUN --mount=target=. \
     --mount=type=cache,target=/root/.cache/go-build \
     sh ./build/docker/crossbuild.sh
diff --git a/build/docker/crossbuild.sh b/build/docker/crossbuild.sh
index 3e5e3eb04..5ab09793d 100644
--- a/build/docker/crossbuild.sh
+++ b/build/docker/crossbuild.sh
@@ -1,32 +1,67 @@
 #!/bin/sh
-set -ex
+set -e
 
-case $GOARCH in
-  arm64)
-    curl -s https://musl.cc/aarch64-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
-    export CC=aarch64-linux-musl-gcc
-    ;;
+# In order to cross-compile with the multi-stage Docker builds, we need to
+# ensure that the suitable toolchain for cross-compiling is installed. Since
+# the images are Alpine-based, we will use musl. Download and install the
+# toolchain inside the build container.
 
-  amd64)
-    curl -s https://musl.cc/x86_64-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
-    export CC=x86_64-linux-musl-gcc
-    ;;
+USERARCH=`go env GOARCH`
+GOARCH="$TARGETARCH"
+GOOS="linux"
 
-  386)
-    curl -s https://musl.cc/i686-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
-    export CC=i686-linux-musl-gcc
-    ;;
+echo "Target arch: $TARGETARCH"
+echo "User arch:   $USERARCH"
 
-  arm)
-    curl -s https://musl.cc/armv7l-linux-musleabihf-cross.tgz | tar xz --strip-components=1 -C /usr
-    export CC=armv7l-linux-musleabihf-gcc
-    ;;
+if [ "$TARGETARCH" != "$USERARCH" ]; then
+    echo "Cross compile"
+    case $GOARCH in
+    arm64)
+        curl -s https://musl.cc/aarch64-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
+        export CC=aarch64-linux-musl-gcc
+        ;;
 
-  *)
-    echo "Unknown GOARCH=${GOARCH}"
-    exit 1
-    ;;
-esac
+    amd64)
+        curl -s https://musl.cc/x86_64-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
+        export CC=x86_64-linux-musl-gcc
+        ;;
 
+    386)
+        curl -s https://musl.cc/i686-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
+        export CC=i686-linux-musl-gcc
+        ;;
+
+    arm)
+        curl -s https://musl.cc/armv7l-linux-musleabihf-cross.tgz | tar xz --strip-components=1 -C /usr
+        export CC=armv7l-linux-musleabihf-gcc
+        ;;
+
+    s390x)
+        curl -s https://musl.cc/s390x-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
+        export CC=s390x-linux-musl-gcc
+        ;;
+
+    ppc64le)
+        curl -s https://musl.cc/powerpc64le-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
+        export CC=powerpc64le-linux-musl-gcc
+        ;;
+
+    riscv64)
+        curl -s https://musl.cc/riscv64-linux-musl-cross.tgz | tar xz --strip-components=1 -C /usr
+        export CC=riscv64-linux-musl-gcc
+        ;;
+
+    *)
+        echo "Unsupported GOARCH=${GOARCH}"
+        exit 1
+        ;;
+    esac
+else
+    echo "Native compile"
+fi
+
+# Output the go environment just in case it is useful for debugging.
 go env
-CGO_ENABLED=1 go build -v -ldflags="-linkmode external -extldflags -static ${FLAGS}" -trimpath -o /out/ ./cmd/...
\ No newline at end of file
+
+# Build Dendrite and tools, statically linking them.
+CGO_ENABLED=1 go build -v -ldflags="-linkmode external -extldflags -static ${FLAGS}" -trimpath -o /out/ ./cmd/...