diff --git a/build.yml b/build.yml
index 36a889d..fddb235 100644
--- a/build.yml
+++ b/build.yml
@@ -5,7 +5,7 @@ build:
     tester:
       name: tester
       dockerfile: Dockerfile.tester
-      command: go test
+      command: go test . ./configuration
     crosscompile:
       name: crosscompile
       depends_on:
diff --git a/build/builder.go b/build/builder.go
index cf586e3..51cc89a 100644
--- a/build/builder.go
+++ b/build/builder.go
@@ -439,14 +439,26 @@ func (b *Builder) BuildStep(step *Step, step_number int) error {
 			permMap := make(map[string]int)
 			if b.Conf.UseStatForPermissions {
 				for _, art := range step.Artifacts {
+					// Define stat command for debian and override if told to use another OS
+					statCmd := []string{"stat", "--format='%a'", art.Source}
+					switch b.Conf.OsType {
+					case "redhat": 
+						statCmd = []string{"stat", "--format='%a'", art.Source}
+					case "busybox":
+						statCmd = []string{"stat", "-c", "'%a'", art.Source}
+					case "alpine":
+						statCmd = []string{"stat", "-c", "'%a'", art.Source}
+					}
+
 					execOpts := docker.CreateExecOptions{
 						Container:    container.ID,
 						AttachStdin:  false,
 						AttachStdout: true,
 						AttachStderr: true,
 						Tty:          false,
-						Cmd:          []string{"stat", "--format='%a'", art.Source},
+						Cmd:          statCmd,
 					}
+					b.Conf.Logger.Debugf("Executing inside %s: %s", container.ID, execOpts.Cmd)
 					execObj, err := b.docker.CreateExec(execOpts)
 					if err != nil {
 						return err
@@ -512,6 +524,7 @@ func (b *Builder) BuildStep(step *Step, step_number int) error {
 				Tty:          true,
 				Cmd:          strings.Split(step.Command, " "),
 			}
+			b.Conf.Logger.Debugf("Executing inside %s: %s", container.ID, execOpts.Cmd)
 			execObj, err := b.docker.CreateExec(execOpts)
 			if err != nil {
 				return err
@@ -705,12 +718,23 @@ func (b *Builder) copyToHost(a *Artifact, container string, perms map[string]int
 }
 
 func (b *Builder) createContainer(step *Step) (*docker.Container, error) {
+	// Define shell for debian and override if another OS is specified
+	shell := []string{"/bin/bash"}
+	switch b.Conf.OsType {
+	case "redhat":
+		shell = []string{"/bin/bash"}
+	case "busybox":
+		shell = []string{"/bin/sh"}
+	case "alpine":
+		shell = []string{"/bin/sh"}
+	}
+
 	config := docker.Config{
 		AttachStdout: true,
 		AttachStdin:  false,
 		AttachStderr: true,
 		Image:        b.uniqueStepName(step),
-		Cmd:          []string{"/bin/bash"},
+		Cmd:          shell,
 		Tty:          true,
 	}
 
diff --git a/configuration/config.go b/configuration/config.go
index ecb0823..4c42e2a 100644
--- a/configuration/config.go
+++ b/configuration/config.go
@@ -14,6 +14,15 @@ type TupleItem struct {
 
 type TupleArray []TupleItem
 
+// Recognized OS type for --os switch.
+// Needs to agree with builder.go
+var OsTypes = []string{
+	"debian",
+	"redhat",
+	"busybox",
+	"alpine",
+}
+
 // Config stores application configurations
 type Config struct {
 	Buildfile                         string
@@ -36,6 +45,7 @@ type Config struct {
 	UseTLS                            bool
 	UseStatForPermissions             bool
 	FroceRmImages                     bool
+	OsType                            string
 	ApiPort                           int
 	ApiBinding                        string
 	SecretService                     bool
@@ -79,3 +89,12 @@ func (i *TupleArray) Find(key string) string {
 func CreateConfig() Config {
 	return Config{}
 }
+
+func (c *Config) ValidateOsType() bool {
+	for _, os := range OsTypes {
+		if c.OsType == os {
+			return true
+		}
+	}
+	return false
+}
diff --git a/configuration/config_test.go b/configuration/config_test.go
new file mode 100644
index 0000000..9dcf008
--- /dev/null
+++ b/configuration/config_test.go
@@ -0,0 +1,50 @@
+package configuration_test
+
+import (
+  . "github.com/onsi/ginkgo"
+  . "github.com/onsi/gomega"
+  "testing"
+  "github.com/cloud66/habitus/configuration"
+)
+
+var _ = Describe("Config", func() {
+  var c configuration.Config
+
+  BeforeEach(func() {
+    c = configuration.CreateConfig()
+  })
+
+  Describe("--os allowed values", func() {
+    It("should accept debian", func() {
+      c.OsType = "debian"
+      Expect(c.ValidateOsType()).To(Equal(true))
+    })
+
+    It("should accept redhat", func() {
+      c.OsType = "redhat"
+      Expect(c.ValidateOsType()).To(Equal(true))
+    })
+
+    It("should accept alpine", func() {
+      c.OsType = "alpine"
+      Expect(c.ValidateOsType()).To(Equal(true))
+    })
+
+    It("should accept busybox", func() {
+      c.OsType = "busybox"
+      Expect(c.ValidateOsType()).To(Equal(true))
+    })
+
+    It("should not accept msdos", func() {
+      c.OsType = "msdos"
+      Expect(c.ValidateOsType()).To(Equal(false))
+    })
+  })
+
+})
+
+
+func ConfigTest(t *testing.T) {
+  RegisterFailHandler(Fail)
+  RunSpecs(t, "Habitus Config Suite")
+}
diff --git a/main.go b/main.go
index 4c4152c..96c653c 100644
--- a/main.go
+++ b/main.go
@@ -74,6 +74,7 @@ func main() {
 	flag.BoolVar(&config.NoSquash, "no-cleanup", false, "Skip cleanup commands for this run. Used for debugging")
 	flag.BoolVar(&config.FroceRmImages, "force-rmi", false, "Force remove of unwanted images")
 	flag.BoolVar(&config.NoPruneRmImages, "noprune-rmi", false, "No pruning of unwanted images")
+	flag.StringVar(&config.OsType, "os", "debian", "Specify the OS that the build occurs in")
 	flag.BoolVar(&flagShowHelp, "help", false, "Display the help")
 	flag.BoolVar(&flagShowVersion, "version", false, "Display version information")
 	flag.IntVar(&config.ApiPort, "port", 8080, "Port to server the API")
@@ -111,6 +112,13 @@ func main() {
 		return
 	}
 
+	// The -os flag allows free form text. Validate what was specified
+	if !config.ValidateOsType() {
+		fmt.Println("Invalid OS name")
+		fmt.Println("Please choose from ", configuration.OsTypes)
+		return
+	}
+
 	level, err := logging.LogLevel(flagLevel)
 	if err != nil {
 		fmt.Println("Invalid log level value. Falling back to debug")