diff --git a/solver/llbsolver/file/user.go b/solver/llbsolver/file/user_linux.go
similarity index 100%
rename from solver/llbsolver/file/user.go
rename to solver/llbsolver/file/user_linux.go
diff --git a/solver/llbsolver/file/user_nolinux.go b/solver/llbsolver/file/user_nolinux.go
new file mode 100644
index 000000000..dc2bb7fc3
--- /dev/null
+++ b/solver/llbsolver/file/user_nolinux.go
@@ -0,0 +1,14 @@
+// +build !linux
+
+package file
+
+import (
+	"github.com/moby/buildkit/solver/llbsolver/ops/fileoptypes"
+	"github.com/moby/buildkit/solver/pb"
+	"github.com/pkg/errors"
+	copy "github.com/tonistiigi/fsutil/copy"
+)
+
+func readUser(chopt *pb.ChownOpt, mu, mg fileoptypes.Mount) (*copy.ChownOpt, error) {
+	return nil, errors.New("only implemented in linux")
+}