diff --git a/deploy.go b/deploy.go
index aca0f42..8dcbaaa 100644
--- a/deploy.go
+++ b/deploy.go
@@ -5,52 +5,43 @@
 package main
 
 import (
-	"log"
-
 	"github.com/tsuru/deploy-agent/internal/tsuru"
 	"github.com/tsuru/tsuru/exec"
 )
 
-func build(c tsuru.Client, appName string, cmd []string, fs Filesystem, executor exec.Executor) {
-	log.SetFlags(0)
+func build(c tsuru.Client, appName string, cmd []string, fs Filesystem, executor exec.Executor) error {
 	envs, err := c.GetAppEnvs(appName)
 	if err != nil {
-		log.Fatal(err)
-	}
-	err = execScript(cmd, envs, nil, fs, executor)
-	if err != nil {
-		log.Fatal(err)
+		return err
 	}
+	return execScript(cmd, envs, nil, fs, executor)
 }
 
-func deploy(c tsuru.Client, appName string, fs Filesystem, executor exec.Executor) {
-	log.SetFlags(0)
+func deploy(c tsuru.Client, appName string, fs Filesystem, executor exec.Executor) error {
 	var yamlData tsuru.TsuruYaml
 	envs, err := c.RegisterUnit(appName, yamlData)
 	if err != nil {
-		log.Fatal(err)
+		return err
 	}
 	diff, firstDeploy, err := readDiffDeploy(fs)
 	if !firstDeploy || err != nil {
 		err = c.SendDiffDeploy(diff, appName)
 		if err != nil {
-			log.Fatal(err)
+			return err
 		}
 	}
 	yamlData, err = loadTsuruYaml(fs)
 	if err != nil {
-		log.Fatal(err)
+		return err
 	}
 	err = buildHooks(yamlData, envs, fs, executor)
 	if err != nil {
-		log.Fatal(err)
+		return err
 	}
 	err = loadProcesses(&yamlData, fs)
 	if err != nil {
-		log.Fatal(err)
+		return err
 	}
 	_, err = c.RegisterUnit(appName, yamlData)
-	if err != nil {
-		log.Fatal(err)
-	}
+	return err
 }
diff --git a/deploy_test.go b/deploy_test.go
index 5dd0376..f156b0a 100644
--- a/deploy_test.go
+++ b/deploy_test.go
@@ -30,7 +30,8 @@ func (s *S) TestBuild(c *check.C) {
 		URL:   server.URL,
 		Token: "fake-token",
 	}
-	build(client, "app1", []string{"ls"}, s.fs, s.exec)
+	err := build(client, "app1", []string{"ls"}, s.fs, s.exec)
+	c.Assert(err, check.IsNil)
 }
 
 func (s *S) TestDeploy(c *check.C) {
@@ -72,5 +73,6 @@ func (s *S) TestDeploy(c *check.C) {
 		URL:   server.URL,
 		Token: "fake-token",
 	}
-	deploy(client, "app1", s.fs, s.exec)
+	err = deploy(client, "app1", s.fs, s.exec)
+	c.Assert(err, check.IsNil)
 }
diff --git a/main.go b/main.go
index 2bba032..75806f5 100644
--- a/main.go
+++ b/main.go
@@ -97,18 +97,25 @@ func main() {
 		}()
 	}
 
+	var err error
 	switch command[len(command)-1] {
 	case "build":
-		build(c, appName, command[:len(command)-1], filesystem, executor)
+		err = build(c, appName, command[:len(command)-1], filesystem, executor)
 	case "deploy-only":
-		deploy(c, appName, filesystem, executor)
+		err = deploy(c, appName, filesystem, executor)
 	case "deploy":
 		// backward compatibility with tsuru < 1.4.0
 		command = command[:len(command)-1]
 		fallthrough
 	default:
-		build(c, appName, command, filesystem, executor)
-		deploy(c, appName, filesystem, executor)
+		err = build(c, appName, command, filesystem, executor)
+		if err != nil {
+			break
+		}
+		err = deploy(c, appName, filesystem, executor)
+	}
+	if err != nil {
+		fatal("[deploy-agent] error: %v", err)
 	}
 }