diff --git a/src/comm/comm.go b/src/comm/comm.go
index 5a72547..4e7966c 100644
--- a/src/comm/comm.go
+++ b/src/comm/comm.go
@@ -41,6 +41,7 @@ func (c *Comm) Close() {
 
 func (c *Comm) Write(b []byte) (int, error) {
 	c.writer.Write([]byte(fmt.Sprintf("%0.6d", len(b))))
+	c.writer.Flush()
 	n, err := c.writer.Write(b)
 	if n != len(b) {
 		err = fmt.Errorf("wanted to write %d but wrote %d", n, len(b))