diff --git a/ui/build/build.go b/ui/build/build.go
index ea86782..95d7831 100644
--- a/ui/build/build.go
+++ b/ui/build/build.go
@@ -427,6 +427,9 @@
 	if config.Checkbuild() {
 		what |= RunBuildTests
 	}
+	if value, ok := config.environ.Get("RUN_BUILD_TESTS"); ok && value == "true" {
+		what |= RunBuildTests
+	}
 	if !config.SkipConfig() {
 		what |= RunProductConfig
 	} else {
diff --git a/ui/build/test_build.go b/ui/build/test_build.go
index 7a2fd16..87bec93 100644
--- a/ui/build/test_build.go
+++ b/ui/build/test_build.go
@@ -76,8 +76,10 @@
 	// treated as an source file.
 	dexpreoptConfigFilePath := filepath.Join(outDir, "soong", "dexpreopt.config")
 
-	// out/build_date.txt is considered a "source file"
+	// out/build_(date|hostname|number).txt is considered a "source file"
 	buildDatetimeFilePath := filepath.Join(outDir, "build_date.txt")
+	buildHostnameFilePath := filepath.Join(outDir, "soong", "build_hostname.txt")
+	buildNumberFilePath := filepath.Join(outDir, "soong", "build_number.txt")
 
 	// release-config files are generated from the initial lunch or Kati phase
 	// before running soong and ninja.
@@ -102,6 +104,8 @@
 			line == extraVariablesFilePath ||
 			line == dexpreoptConfigFilePath ||
 			line == buildDatetimeFilePath ||
+			line == buildHostnameFilePath ||
+			line == buildNumberFilePath ||
 			strings.HasPrefix(line, releaseConfigDir) ||
 			buildFingerPrintFilePattern.MatchString(line) {
 			// Leaf node is in one of Soong's bootstrap directories, which do not have