diff --git a/dashboard/builder/exec.go b/dashboard/builder/exec.go
index ddc1e899..1b46ed1c 100644
--- a/dashboard/builder/exec.go
+++ b/dashboard/builder/exec.go
@@ -22,6 +22,7 @@ func run(cmd *exec.Cmd, opts ...runOpt) error {
 		log.Printf("running %v in %v", a.cmd.Args, a.cmd.Dir)
 	}
 	if err := cmd.Start(); err != nil {
+		log.Printf("failed to start command %v: %v", a.cmd.Args, err)
 		return err
 	}
 	err := timeout(a.timeout, cmd.Wait)
diff --git a/dashboard/builder/main.go b/dashboard/builder/main.go
index 211d8af5..9e7c1ed3 100644
--- a/dashboard/builder/main.go
+++ b/dashboard/builder/main.go
@@ -421,6 +421,7 @@ func (b *Builder) buildHash(hash string) error {
 
 	buildLog, runTime, err := b.buildRepoOnHash(workpath, hash, b.buildCmd())
 	if err != nil {
+		log.Printf("%s failed at %v: %v", b.name, hash, err)
 		// record failure
 		return b.recordResult(false, "", hash, "", buildLog, runTime)
 	}