diff --git a/legacy/builder/builder_utils/utils.go b/legacy/builder/builder_utils/utils.go
index f324940cfdb..af5349bf5bd 100644
--- a/legacy/builder/builder_utils/utils.go
+++ b/legacy/builder/builder_utils/utils.go
@@ -38,15 +38,6 @@ import (
 
 var tr = i18n.Tr
 
-func findAllFilesInFolder(sourcePath *paths.Path, recurse bool) (paths.PathList, error) {
-	if !recurse {
-		return sourcePath.ReadDir(paths.FilterOutDirectories())
-	}
-	return sourcePath.ReadDirRecursiveFiltered(
-		utils.FilterOutSCCS,
-		paths.FilterOutDirectories())
-}
-
 // FilesAreOlderThan returns true if the given files are older than target.
 func FilesAreOlderThan(files paths.PathList, target *paths.Path) (bool, error) {
 	targetStat, err := target.Stat()
@@ -329,7 +320,7 @@ func removeEndingBackSlash(s string) string {
 }
 
 func CoreOrReferencedCoreHasChanged(corePath, targetCorePath, targetFile *paths.Path) bool {
-	files, err := findAllFilesInFolder(corePath, true)
+	files, err := utils.FindFilesInFolder(corePath, true)
 	if err != nil {
 		return true
 	}
@@ -345,7 +336,7 @@ func CoreOrReferencedCoreHasChanged(corePath, targetCorePath, targetFile *paths.
 }
 
 func TXTBuildRulesHaveChanged(corePath, targetCorePath, targetFile *paths.Path) bool {
-	files, err := utils.FindFilesInFolder(corePath, true, []string{".txt"})
+	files, err := utils.FindFilesInFolder(corePath, true, ".txt")
 	if err != nil {
 		return true
 	}
diff --git a/legacy/builder/container_find_includes.go b/legacy/builder/container_find_includes.go
index 4c78e18ce18..5d849b927ed 100644
--- a/legacy/builder/container_find_includes.go
+++ b/legacy/builder/container_find_includes.go
@@ -427,7 +427,7 @@ func queueSourceFilesFromFolder(ctx *types.Context, sourceFileQueue *types.Uniqu
 	for k := range globals.SourceFilesValidExtensions {
 		sourceFileExtensions = append(sourceFileExtensions, k)
 	}
-	filePaths, err := utils.FindFilesInFolder(folder, recurse, sourceFileExtensions)
+	filePaths, err := utils.FindFilesInFolder(folder, recurse, sourceFileExtensions...)
 	if err != nil {
 		return errors.WithStack(err)
 	}
diff --git a/legacy/builder/create_cmake_rule.go b/legacy/builder/create_cmake_rule.go
index 9a2bbecef60..acbce09e2cb 100644
--- a/legacy/builder/create_cmake_rule.go
+++ b/legacy/builder/create_cmake_rule.go
@@ -222,7 +222,7 @@ func (s *ExportProjectCMake) Run(ctx *types.Context) error {
 		}
 
 		// Remove stray folders contining incompatible or not needed libraries archives
-		files, _ := utils.FindFilesInFolder(libDir.Join("src"), true, validStaticLibExtensions)
+		files, _ := utils.FindFilesInFolder(libDir.Join("src"), true, validStaticLibExtensions...)
 		for _, file := range files {
 			staticLibDir := file.Parent()
 			if !isStaticLib || !strings.Contains(staticLibDir.String(), mcu) {
@@ -251,7 +251,7 @@ func (s *ExportProjectCMake) Run(ctx *types.Context) error {
 	}
 
 	// remove "#line 1 ..." from exported c_make folder sketch
-	sketchFiles, _ := utils.FindFilesInFolder(cmakeFolder.Join("sketch"), false, validExportExtensions)
+	sketchFiles, _ := utils.FindFilesInFolder(cmakeFolder.Join("sketch"), false, validExportExtensions...)
 
 	for _, file := range sketchFiles {
 		input, err := file.ReadFile()
@@ -285,11 +285,11 @@ func (s *ExportProjectCMake) Run(ctx *types.Context) error {
 	extractCompileFlags(ctx, "recipe.cpp.o.pattern", &defines, &dynamicLibsFromGccMinusL, &linkerflags, &linkDirectories)
 
 	// Extract folders with .h in them for adding in include list
-	headerFiles, _ := utils.FindFilesInFolder(cmakeFolder, true, validHeaderExtensions)
+	headerFiles, _ := utils.FindFilesInFolder(cmakeFolder, true, validHeaderExtensions...)
 	foldersContainingHeaders := findUniqueFoldersRelative(headerFiles.AsStrings(), cmakeFolder.String())
 
 	// Extract folders with .a in them for adding in static libs paths list
-	staticLibs, _ := utils.FindFilesInFolder(cmakeFolder, true, validStaticLibExtensions)
+	staticLibs, _ := utils.FindFilesInFolder(cmakeFolder, true, validStaticLibExtensions...)
 
 	// Generate the CMakeLists global file
 
diff --git a/legacy/builder/utils/utils.go b/legacy/builder/utils/utils.go
index 0c39c0efdc2..102b007883f 100644
--- a/legacy/builder/utils/utils.go
+++ b/legacy/builder/utils/utils.go
@@ -126,14 +126,19 @@ func ExecCommand(ctx *types.Context, command *exec.Cmd, stdout int, stderr int)
 	return outbytes, errbytes, errors.WithStack(err)
 }
 
-func FindFilesInFolder(dir *paths.Path, recurse bool, extensions []string) (paths.PathList, error) {
+func FindFilesInFolder(dir *paths.Path, recurse bool, extensions ...string) (paths.PathList, error) {
 	fileFilter := paths.AndFilter(
-		paths.FilterSuffixes(extensions...),
 		FilterOutHiddenFiles,
 		FilterOutSCCS,
 		paths.FilterOutDirectories(),
 		FilterReadableFiles,
 	)
+	if len(extensions) > 0 {
+		fileFilter = paths.AndFilter(
+			paths.FilterSuffixes(extensions...),
+			fileFilter,
+		)
+	}
 	if recurse {
 		dirFilter := paths.AndFilter(
 			FilterOutHiddenFiles,