diff --git a/cmd/jade/jade.go b/cmd/jade/jade.go
index 06dab55..656d512 100644
--- a/cmd/jade/jade.go
+++ b/cmd/jade/jade.go
@@ -39,12 +39,14 @@ type WriterAsBuffer struct {
 	io.Writer
 }
 
-func (w *WriterAsBuffer) WriteString(s string) {
-	w.Write([]byte(s))
+func (w *WriterAsBuffer) WriteString(s string) (n int, err error) {
+	n, err = w.Write([]byte(s))
+	return
 }
 
-func (w *WriterAsBuffer) WriteByte(b byte) {
-	w.Write([]byte{b})
+func (w *WriterAsBuffer) WriteByte(b byte) (err error) {
+	_, err = w.Write([]byte{b})
+	return
 }
 
 type stringer interface {