diff --git a/internal/flatten.go b/internal/flatten.go
index bf8ad954..8ba9e8b4 100644
--- a/internal/flatten.go
+++ b/internal/flatten.go
@@ -22,7 +22,7 @@ Spec can be a path to a file, a URL or '-' to read standard input.
 		Args: cobra.ExactArgs(1),
 		RunE: func(cmd *cobra.Command, args []string) error {
 
-			flags.source = load.GetSource(args[0])
+			flags.spec = load.GetSource(args[0])
 
 			// by now flags have been parsed successfully so we don't need to show usage on any errors
 			cmd.Root().SilenceUsage = true
@@ -49,9 +49,9 @@ func runFlatten(flags *FlattenFlags, stdout io.Writer) *ReturnError {
 
 	loader := openapi3.NewLoader()
 	loader.IsExternalRefsAllowed = true
-	spec, err := load.LoadSpecInfo(loader, flags.source)
+	spec, err := load.LoadSpecInfo(loader, flags.spec)
 	if err != nil {
-		return getErrFailedToLoadSpec("original", flags.source, err)
+		return getErrFailedToLoadSpec("original", flags.spec, err)
 	}
 
 	// TODO: get the original format of the spec
@@ -59,7 +59,7 @@ func runFlatten(flags *FlattenFlags, stdout io.Writer) *ReturnError {
 
 	flatSpec, err := flatten.MergeSpec(spec.Spec)
 	if err != nil {
-		return getErrFailedToFlattenSpec("original", flags.source, err)
+		return getErrFailedToFlattenSpec("original", flags.spec, err)
 	}
 
 	if returnErr := outputFlattenedSpec(format, stdout, flatSpec); returnErr != nil {
diff --git a/internal/flatten_flags.go b/internal/flatten_flags.go
index 8ba9c647..9b5f61e3 100644
--- a/internal/flatten_flags.go
+++ b/internal/flatten_flags.go
@@ -3,7 +3,7 @@ package internal
 import "github.com/tufin/oasdiff/load"
 
 type FlattenFlags struct {
-	source                   load.Source
+	spec                     load.Source
 	format                   string
 	circularReferenceCounter int
 }