diff --git a/lib/bash/app/lib_app.sh b/lib/bash/app/lib_app.sh
index 7dc6e9d..863b03a 100644
--- a/lib/bash/app/lib_app.sh
+++ b/lib/bash/app/lib_app.sh
@@ -528,7 +528,7 @@ base_app_config_load() {
     fi
     for key in "${__base_bash_libs_app_keys[@]+${__base_bash_libs_app_keys[@]}}"; do
         env_name="${__base_bash_libs_app_config["$model|$key|env"]-}"
-        if [[ -n "$env_name" && -n "${!env_name+x}" ]]; then
+        if [[ -n "$env_name" && -n "${!env_name-}" ]]; then
             __base_bash_libs_app_set_value__ "$model" "$key" "${!env_name}" environment || {
                 status=$?
                 __base_bash_libs_app_clear_staged_config__
diff --git a/lib/bash/app/tests/lib_app.bats b/lib/bash/app/tests/lib_app.bats
index fd9bb16..d315704 100644
--- a/lib/bash/app/tests/lib_app.bats
+++ b/lib/bash/app/tests/lib_app.bats
@@ -7,7 +7,7 @@ setup() {
     source "$BASE_BASH_DIR/std/lib_std.sh"
     source "$BASE_BASH_DIR/cli/lib_cli.sh"
     source "$BASE_BASH_DIR/app/lib_app.sh"
-    unset APP_TEST_MODE APP_TEST_SECRET
+    unset APP_TEST_MODE APP_TEST_SECRET APP_TEST_TIMEOUT
 }
 
 validate_test_label() {
@@ -65,6 +65,21 @@ assert_demo_snapshot() {
     [ "$value" = cli-secret ]
 }
 
+@test "empty environment bindings do not override file configuration" {
+    local project_file="$TEST_TMPDIR/project.conf" value source
+
+    base_app_init empty_env name=empty-env
+    base_app_config_define empty_env timeout integer default=10 env=APP_TEST_TIMEOUT
+    printf 'timeout=30\n' > "$project_file"
+    export APP_TEST_TIMEOUT=
+
+    base_app_config_load empty_env --project "$project_file"
+    base_app_config_get empty_env timeout value
+    base_app_config_provenance empty_env timeout source
+    [ "$value" -eq 30 ]
+    [ "$source" = project ]
+}
+
 @test "enum validation preserves a caller variable with the internal scratch name" {
     local -a __base_bash_libs_app_enum_values=(caller-owned)