diff --git a/go.mod b/go.mod
index 7c61013..db4dfa7 100644
--- a/go.mod
+++ b/go.mod
@@ -2,4 +2,7 @@ module gitlab.com/bboehmke/raspi-alpine-builder
 
 go 1.13
 
-require github.com/stretchr/testify v1.4.0
+require (
+	github.com/GehirnInc/crypt v0.0.0-20190301055215-6c0105aabd46
+	github.com/stretchr/testify v1.4.0
+)
diff --git a/go.sum b/go.sum
index a65f495..eb9f130 100644
--- a/go.sum
+++ b/go.sum
@@ -1,13 +1,14 @@
+github.com/GehirnInc/crypt v0.0.0-20190301055215-6c0105aabd46 h1:rs0kDBt2zF4/CM9rO5/iH+U22jnTygPlqWgX55Ufcxg=
+github.com/GehirnInc/crypt v0.0.0-20190301055215-6c0105aabd46/go.mod h1:kC29dT1vFpj7py2OvG1khBdQpo3kInWP+6QipLbdngo=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/iris-contrib/go.uuid v2.0.0+incompatible/go.mod h1:iz2lgM/1UnEf1kP0L/+fafWORmlnuysV2EMP8MW+qe0=
-github.com/kataras/iris v11.1.1+incompatible/go.mod h1:ki9XPua5SyAJbIxDdsssxevgGrbpBmmvoQmo/A0IodY=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
diff --git a/system.go b/system.go
new file mode 100644
index 0000000..ca32547
--- /dev/null
+++ b/system.go
@@ -0,0 +1,84 @@
+package alpine_builder
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/GehirnInc/crypt"
+	_ "github.com/GehirnInc/crypt/sha256_crypt"
+)
+
+// system configurations
+var systemShadow = "/data/etc/shadow"
+var systemDropbearConfig = "/data/etc/dropbear/dropbear.conf"
+var systemDropbearRestart = "rc-service dropbear start"
+var systemShutdown = "poweroff"
+var systemReboot = "reboot"
+
+// SystemSetRootPassword update shadow file
+func SystemSetRootPassword(password string) error {
+	crypter := crypt.SHA256.New()
+
+	// generate password line
+	hash, err := crypter.Generate([]byte(password), nil)
+	if err != nil {
+		return fmt.Errorf("failed to generate hash: %w", err)
+	}
+	line := fmt.Sprintf("root:%s:0:0:::::", hash)
+
+	// write shadow file
+	return ioutil.WriteFile(systemShadow, []byte(line), os.ModePerm)
+}
+
+// SystemEnableSSH server
+func SystemEnableSSH() error {
+	err := ioutil.WriteFile(systemDropbearConfig, []byte("DROPBEAR_OPTS=\"\""), os.ModePerm)
+	if err != nil {
+		return fmt.Errorf("failed to write ssh config: %w", err)
+	}
+
+	cmdSplit := strings.Split(systemDropbearRestart, " ")
+	cmd := exec.Command(cmdSplit[0], cmdSplit[1:]...)
+	err = cmd.Run()
+	if err != nil {
+		return fmt.Errorf("failed to restart ssh server: %w", err)
+	}
+	return nil
+}
+
+// SystemDisableSSH server
+func SystemDisableSSH() error {
+	err := ioutil.WriteFile(systemDropbearConfig, []byte("DROPBEAR_OPTS=\"-p 127.0.0.1:22\""), os.ModePerm)
+	if err != nil {
+		return fmt.Errorf("failed to write ssh config: %w", err)
+	}
+
+	cmdSplit := strings.Split(systemDropbearRestart, " ")
+	cmd := exec.Command(cmdSplit[0], cmdSplit[1:]...)
+	err = cmd.Run()
+	if err != nil {
+		return fmt.Errorf("failed to restart ssh server: %w", err)
+	}
+	return nil
+}
+
+func SystemShutdown() error {
+	cmd := exec.Command(systemShutdown)
+	err := cmd.Run()
+	if err != nil {
+		return fmt.Errorf("failed to start system shutdown: %w", err)
+	}
+	return nil
+}
+
+func SystemReboot() error {
+	cmd := exec.Command(systemReboot)
+	err := cmd.Run()
+	if err != nil {
+		return fmt.Errorf("failed to start system reboot: %w", err)
+	}
+	return nil
+}
diff --git a/system_test.go b/system_test.go
new file mode 100644
index 0000000..79b4d64
--- /dev/null
+++ b/system_test.go
@@ -0,0 +1,75 @@
+package alpine_builder
+
+import (
+	"io/ioutil"
+	"os"
+	"strings"
+	"testing"
+
+	"github.com/GehirnInc/crypt"
+	_ "github.com/GehirnInc/crypt/sha256_crypt"
+	"github.com/stretchr/testify/assert"
+)
+
+func init() {
+	systemShadow = "test_shadow"
+	systemDropbearConfig = "test_dropbear"
+	systemDropbearRestart = "restart_dropbear_command"
+	systemReboot = "reboot_command"
+	systemShutdown = "shutdown_command"
+}
+
+func TestSystemSetRootPassword(t *testing.T) {
+	ass := assert.New(t)
+
+	ass.NoError(SystemSetRootPassword("password"))
+
+	data, err := ioutil.ReadFile(systemShadow)
+	ass.NoError(err)
+	hash := strings.Split(string(data), ":")[1]
+
+	crypter := crypt.SHA256.New()
+	ass.NoError(crypter.Verify(hash, []byte("password")))
+
+	_ = os.Remove(systemShadow)
+}
+
+func TestSystemEnableSSH(t *testing.T) {
+	ass := assert.New(t)
+
+	ass.EqualError(SystemEnableSSH(), "failed to restart ssh server: exec: \"restart_dropbear_command\": executable file not found in $PATH")
+
+	data, err := ioutil.ReadFile(systemDropbearConfig)
+	ass.NoError(err)
+
+	ass.Equal("DROPBEAR_OPTS=\"\"", string(data))
+
+	_ = os.Remove(systemDropbearConfig)
+}
+
+func TestSystemDisableSSH(t *testing.T) {
+	ass := assert.New(t)
+
+	ass.EqualError(SystemDisableSSH(), "failed to restart ssh server: exec: \"restart_dropbear_command\": executable file not found in $PATH")
+
+	data, err := ioutil.ReadFile(systemDropbearConfig)
+	ass.NoError(err)
+
+	ass.Equal("DROPBEAR_OPTS=\"-p 127.0.0.1:22\"", string(data))
+
+	_ = os.Remove(systemDropbearConfig)
+}
+
+func TestSystemReboot(t *testing.T) {
+	ass := assert.New(t)
+
+	ass.EqualError(SystemReboot(),
+		"failed to start system reboot: exec: \"reboot_command\": executable file not found in $PATH")
+}
+
+func TestSystemShutdown(t *testing.T) {
+	ass := assert.New(t)
+
+	ass.EqualError(SystemShutdown(),
+		"failed to start system shutdown: exec: \"shutdown_command\": executable file not found in $PATH")
+}