diff --git a/tests/functional/common/vars-and-functions.sh.in b/tests/functional/common/vars-and-functions.sh.in
index 848988af9..02773bf60 100644
--- a/tests/functional/common/vars-and-functions.sh.in
+++ b/tests/functional/common/vars-and-functions.sh.in
@@ -45,6 +45,7 @@ if [[ -n "${NIX_DAEMON_PACKAGE:-}" ]]; then
   DAEMON_PATH="${NIX_DAEMON_PACKAGE}/bin:$DAEMON_PATH"
 fi
 coreutils=@coreutils@
+lsof=@lsof@
 
 export dot=@dot@
 export SHELL="@bash@"
diff --git a/tests/functional/flakes/develop.sh b/tests/functional/flakes/develop.sh
index 59f731239..db23ca0c0 100644
--- a/tests/functional/flakes/develop.sh
+++ b/tests/functional/flakes/develop.sh
@@ -54,7 +54,7 @@ BASH_INTERACTIVE_EXECUTABLE="$PWD/bash-interactive/bin/bash"
 [[ "$(
     nix develop --no-write-lock-file .#hello <<EOF
 export PATH="$PATH"
-ps --pid $$ --format exe --no-headers
+$lsof -a -d txt -p \$$ 2>&1 | grep -o '/.*/bash'
 EOF
 )" -ef "$BASH_INTERACTIVE_EXECUTABLE" ]]