diff --git a/cmd/multiproduct_kati/main.go b/cmd/multiproduct_kati/main.go
index e0f8caa..20f146a 100644
--- a/cmd/multiproduct_kati/main.go
+++ b/cmd/multiproduct_kati/main.go
@@ -433,7 +433,7 @@
 	config := build.NewConfig(ctx, args...)
 	config.Environment().Set("OUT_DIR", outDir)
 	if !*keepArtifacts {
-		config.Environment().Set("EMPTY_NINJA_FILE", "true")
+		config.SetEmptyNinjaFile(true)
 	}
 	build.FindSources(ctx, config, mpctx.Finder)
 	config.Lunch(ctx, product, *buildVariant)
diff --git a/ui/build/config.go b/ui/build/config.go
index 1d1f71f..3ebde0d 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -72,6 +72,9 @@
 	// During Bazel execution, Bazel cannot write outside OUT_DIR.
 	// So if DIST_DIR is set to an external dir (outside of OUT_DIR), we need to rig it temporarily and then migrate files at the end of the build.
 	riggedDistDirForBazel string
+
+	// Set by multiproduct_kati
+	emptyNinjaFile bool
 }
 
 const srcDirFileCheck = "build/soong/root.bp"
@@ -203,9 +206,6 @@
 		"ANDROID_DEV_SCRIPTS",
 		"ANDROID_EMULATOR_PREBUILTS",
 		"ANDROID_PRE_BUILD_PATHS",
-
-		// Only set in multiproduct_kati after config generation
-		"EMPTY_NINJA_FILE",
 	)
 
 	if ret.UseGoma() || ret.ForceUseGoma() {
@@ -1189,3 +1189,11 @@
 func (c *configImpl) BazelMetricsDir() string {
 	return filepath.Join(c.LogsDir(), "bazel_metrics")
 }
+
+func (c *configImpl) SetEmptyNinjaFile(v bool) {
+	c.emptyNinjaFile = v
+}
+
+func (c *configImpl) EmptyNinjaFile() bool {
+	return c.emptyNinjaFile
+}
diff --git a/ui/build/kati.go b/ui/build/kati.go
index 06ec646..dad68fa 100644
--- a/ui/build/kati.go
+++ b/ui/build/kati.go
@@ -136,7 +136,7 @@
 	// information out with --empty_ninja_file.
 	//
 	// From https://github.com/google/kati/commit/87b8da7af2c8bea28b1d8ab17679453d859f96e5
-	if config.Environment().IsEnvTrue("EMPTY_NINJA_FILE") {
+	if config.EmptyNinjaFile() {
 		args = append(args, "--empty_ninja_file")
 	}
 
diff --git a/ui/build/soong.go b/ui/build/soong.go
index cd645eb..7128414 100644
--- a/ui/build/soong.go
+++ b/ui/build/soong.go
@@ -119,6 +119,7 @@
 	args.OutFile = shared.JoinPath(config.SoongOutDir(), ".bootstrap/build.ninja")
 	args.GlobFile = globFile
 	args.GeneratingPrimaryBuilder = true
+	args.EmptyNinjaFile = config.EmptyNinjaFile()
 
 	args.DelveListen = os.Getenv("SOONG_DELVE")
 	if args.DelveListen != "" {