diff --git a/internal/backend_test.go b/internal/backend_test.go
new file mode 100644
index 0000000..a97c7cd
--- /dev/null
+++ b/internal/backend_test.go
@@ -0,0 +1,225 @@
+package internal
+
+import (
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/spf13/viper"
+)
+
+func TestGenerateRepo(t *testing.T) {
+
+	t.Run("empty backend", func(t *testing.T) {
+		b := Backend{
+			name: "empty backend",
+			Type: "",
+		}
+		_, err := b.generateRepo()
+		if err == nil {
+			t.Errorf("Error expected for empty backend type")
+		}
+	})
+
+	t.Run("local backend", func(t *testing.T) {
+		b := Backend{
+			name: "local backend",
+			Type: "local",
+			Path: "/foo/bar",
+		}
+		result, err := b.generateRepo()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result, "/foo/bar")
+	})
+
+	t.Run("local backend with homedir prefix", func(t *testing.T) {
+		b := Backend{
+			name: "local backend",
+			Type: "local",
+			Path: "~/foo/bar",
+		}
+		result, err := b.generateRepo()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result, fmt.Sprintf("%s/foo/bar", os.Getenv("HOME")))
+	})
+
+	t.Run("local backend with config file", func(t *testing.T) {
+		// config file path should always be present from initConfig
+		viper.SetConfigFile("/tmp/.autorestic.yml")
+		defer viper.Reset()
+
+		b := Backend{
+			name: "local backend",
+			Type: "local",
+		}
+		result, err := b.generateRepo()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result, "/tmp")
+	})
+
+	t.Run("rest backend with valid path", func(t *testing.T) {
+		b := Backend{
+			name: "rest backend",
+			Type: "rest",
+			Path: "http://localhost:8000/foo",
+		}
+		result, err := b.generateRepo()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result, "rest:http://localhost:8000/foo")
+	})
+
+	t.Run("rest backend with user", func(t *testing.T) {
+		b := Backend{
+			name: "rest backend",
+			Type: "rest",
+			Path: "http://localhost:8000/foo",
+			Rest: BackendRest{
+				User:     "user",
+				Password: "",
+			},
+		}
+		result, err := b.generateRepo()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result, "rest:http://user@localhost:8000/foo")
+	})
+
+	t.Run("rest backend with user and password", func(t *testing.T) {
+		b := Backend{
+			name: "rest backend",
+			Type: "rest",
+			Path: "http://localhost:8000/foo",
+			Rest: BackendRest{
+				User:     "user",
+				Password: "pass",
+			},
+		}
+		result, err := b.generateRepo()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result, "rest:http://user:pass@localhost:8000/foo")
+	})
+
+	backendTests := []struct {
+		name    string
+		backend Backend
+		want    string
+	}{
+		{name: "b2 backend", backend: Backend{name: "b2", Type: "b2", Path: "foo"}, want: "b2:foo"},
+		{name: "azure backend", backend: Backend{name: "azure", Type: "azure", Path: "foo"}, want: "azure:foo"},
+		{name: "gs backend", backend: Backend{name: "gs", Type: "gs", Path: "foo"}, want: "gs:foo"},
+		{name: "s3 backend", backend: Backend{name: "s3", Type: "s3", Path: "foo"}, want: "s3:foo"},
+		{name: "sftp backend", backend: Backend{name: "sftp", Type: "sftp", Path: "foo"}, want: "sftp:foo"},
+		{name: "rclone backend", backend: Backend{name: "rclone", Type: "rclone", Path: "foo"}, want: "rclone:foo"},
+	}
+
+	for _, tt := range backendTests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := tt.backend.generateRepo()
+			if err != nil {
+				t.Errorf("unexpected error %v", err)
+			}
+			assertEqual(t, got, tt.want)
+		})
+	}
+}
+
+func TestGetEnv(t *testing.T) {
+	t.Run("env in key field", func(t *testing.T) {
+		b := Backend{
+			name: "",
+			Type: "local",
+			Path: "/foo/bar",
+			Key:  "secret123",
+		}
+		result, err := b.getEnv()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result["RESTIC_REPOSITORY"], "/foo/bar")
+		assertEqual(t, result["RESTIC_PASSWORD"], "secret123")
+	})
+
+	t.Run("env in config file", func(t *testing.T) {
+		b := Backend{
+			name: "",
+			Type: "local",
+			Path: "/foo/bar",
+			Env: map[string]string{
+				"B2_ACCOUNT_ID":  "foo123",
+				"B2_ACCOUNT_KEY": "foo456",
+			},
+		}
+		result, err := b.getEnv()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result["RESTIC_REPOSITORY"], "/foo/bar")
+		assertEqual(t, result["RESTIC_PASSWORD"], "")
+		assertEqual(t, result["B2_ACCOUNT_ID"], "foo123")
+		assertEqual(t, result["B2_ACCOUNT_KEY"], "foo456")
+	})
+
+	t.Run("env in Envfile or env vars", func(t *testing.T) {
+		// generate env variables
+		// TODO better way to teardown
+		defer os.Unsetenv("AUTORESTIC_FOO_RESTIC_PASSWORD")
+		defer os.Unsetenv("AUTORESTIC_FOO_B2_ACCOUNT_ID")
+		defer os.Unsetenv("AUTORESTIC_FOO_B2_ACCOUNT_KEY")
+		os.Setenv("AUTORESTIC_FOO_RESTIC_PASSWORD", "secret123")
+		os.Setenv("AUTORESTIC_FOO_B2_ACCOUNT_ID", "foo123")
+		os.Setenv("AUTORESTIC_FOO_B2_ACCOUNT_KEY", "foo456")
+
+		b := Backend{
+			name: "foo",
+			Type: "local",
+			Path: "/foo/bar",
+		}
+		result, err := b.getEnv()
+		if err != nil {
+			t.Errorf("unexpected error %v", err)
+		}
+		assertEqual(t, result["RESTIC_REPOSITORY"], "/foo/bar")
+		assertEqual(t, result["RESTIC_PASSWORD"], "secret123")
+		assertEqual(t, result["B2_ACCOUNT_ID"], "foo123")
+		assertEqual(t, result["B2_ACCOUNT_KEY"], "foo456")
+	})
+}
+
+func TestValidate(t *testing.T) {
+	t.Run("no type given", func(t *testing.T) {
+		b := Backend{
+			name: "foo",
+			Type: "",
+			Path: "/foo/bar",
+		}
+		err := b.validate()
+		if err == nil {
+			t.Error("expected to get error")
+		}
+		assertEqual(t, err.Error(), "Backend \"foo\" has no \"type\"")
+	})
+
+	t.Run("no path given", func(t *testing.T) {
+		b := Backend{
+			name: "foo",
+			Type: "local",
+			Path: "",
+		}
+		err := b.validate()
+		if err == nil {
+			t.Error("expected to get error")
+		}
+		assertEqual(t, err.Error(), "Backend \"foo\" has no \"path\"")
+	})
+}