diff --git a/run_tests.sh b/run_tests.sh
index 435b0ff2..e5d4e585 100755
--- a/run_tests.sh
+++ b/run_tests.sh
@@ -9,10 +9,11 @@ set -Eeuo pipefail
 top="$(dirname "$0")"
 top="$(cd "$top"; pwd)"
 
-if [ -z "${IN_CRATE2NIX_SHELL:-}" -o "${IN_NIX_SHELL:-}" = "impure" ]; then
-  export CACHIX="$(which cachix 2>/dev/null || echo "")"
+if [ -z "${IN_CRATE2NIX_SHELL:-}" ] || [ "${IN_NIX_SHELL:-}" = "impure" ]; then
+  export CACHIX
+  CACHIX="$(which cachix 2>/dev/null || echo "")"
   echo -e "\e[1m=== Entering $top/shell.nix\e[0m" >&2
-  exec nix-shell --keep CACHIX --pure "$top/shell.nix" --run "$(printf "%q " $0 "$@")"
+  exec nix-shell --keep CACHIX --pure "$top/shell.nix" --run "$(printf "%q " "$0" "$@")"
 fi
 
 echo -e "\e[1m=== Parsing opts for $top/run_tests.sh\e[0m" >&2
@@ -25,24 +26,24 @@ options=$(getopt -o '' --long offline,build-test-nixpkgs:,no-cargo-build  -- "$@
     exit 1
 }
 eval set -- "$options"
-NIX_OPTIONS="--option log-lines 100 --show-trace"
-REGENERATE_OPTIONS=""
-NIX_TESTS_OPTIONS="--out-link ./target/nix-result"
+NIX_OPTIONS=( --option log-lines 100 --show-trace )
+REGENERATE_OPTIONS=()
+NIX_TESTS_OPTIONS=( --out-link ./target/nix-result )
 NO_CARGO_BUILD=""
 while true; do
     case "$1" in
     --no-cargo-build)
-        REGENERATE_OPTIONS="$REGENERATE_OPTIONS --no-cargo-build"
+        REGENERATE_OPTIONS+=( --no-cargo-build )
         NO_CARGO_BUILD="1"
         ;;
     --offline)
-        NIX_OPTIONS="$NIX_OPTIONS --option substitute false"
-        REGENERATE_OPTIONS="$REGENERATE_OPTIONS --offline"
+        NIX_OPTIONS+=( --option substitute false )
+        REGENERATE_OPTIONS+=( --offline )
         CACHIX=""
         ;;
     --build-test-nixpkgs)
         shift
-        NIX_TESTS_OPTIONS="$NIX_TESTS_OPTIONS --arg buildTestNixpkgs $1"
+        NIX_TESTS_OPTIONS+=( --arg buildTestNixpkgs $1 )
         ;;
     --)
         shift
@@ -84,9 +85,9 @@ else
     echo "Skipping because of --no-cargo-build"
 fi
 
-../regenerate_cargo_nix.sh $REGENERATE_OPTIONS || {
+../regenerate_cargo_nix.sh "${REGENERATE_OPTIONS[@]}" || {
     echo "==================" >&2
-    echo "$top/regenerate_cargo_nix.sh $REGENERATE_OPTIONS: FAILED" >&2
+    echo "$top/regenerate_cargo_nix.sh ${REGENERATE_OPTIONS[*]}: FAILED" >&2
     exit 3
 }
 
@@ -104,11 +105,11 @@ fi
 cd "$top"
 echo -e "\e[1m=== Building ./tests.nix (= Running Integration Tests)\e[0m" >&2
 rm -rf target/nix-result*
-nix build -L $NIX_OPTIONS $NIX_TESTS_OPTIONS -f ./tests.nix || {
+nix build -L "${NIX_OPTIONS[@]}" "${NIX_TESTS_OPTIONS[@]}" -f ./tests.nix || {
     echo "==================" >&2
     echo "cd $top" >&2
     echo "nix build -L \\" >&2
-    echo "  $NIX_OPTIONS $NIX_TESTS_OPTIONS \\" >&2
+    echo "  ${NIX_OPTIONS[*]} ${NIX_TESTS_OPTIONS[*]} \\" >&2
     echo "   -f ./tests.nix"
     echo "=> FAILED" >&2
     exit 5
@@ -135,7 +136,7 @@ if test -n "${CACHIX:-}" && test -r ~/.config/cachix/cachix.dhall &&\
     echo -e "\e[1m=== Pushing artifacts to eigenvalue.cachix.org \e[0m" >&2
     # we filter for "rust_" to exclude some things that are in the
     # nixos cache anyways
-    nix-store -q -R --include-outputs $(nix-store -q -d target/nix-result* | grep -v crates.io) |\
+    nix-store -q -R --include-outputs "$(nix-store -q -d target/nix-result* | grep -v crates.io)" |\
      grep -e "-rust_" |\
      $CACHIX push eigenvalue
 fi