diff --git a/cmd/app/app.go b/cmd/app/app.go
index 7e67763f..9494fe8b 100644
--- a/cmd/app/app.go
+++ b/cmd/app/app.go
@@ -201,6 +201,20 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 			)
 			continue
 
+		case "ro+":
+			source, target, err := parsePair(value)
+			if err != nil {
+				return nil, err
+			}
+			c.Container.Filesystem = append(c.Container.Filesystem,
+				hst.FilesystemConfigJSON{FilesystemConfig: &hst.FSBind{
+					Target:   target,
+					Source:   source,
+					Optional: true,
+				}},
+			)
+			continue
+
 		case "rw":
 			source, target, err := parsePair(value)
 			if err != nil {
@@ -215,6 +229,20 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 			)
 			continue
 
+		case "dev":
+			source, target, err := parsePair(value)
+			if err != nil {
+				return nil, err
+			}
+			c.Container.Filesystem = append(c.Container.Filesystem,
+				hst.FilesystemConfigJSON{FilesystemConfig: &hst.FSBind{
+					Target: target,
+					Source: source,
+					Device: true,
+				}},
+			)
+			continue
+
 		case "own":
 			c.SessionBus.Own = append(c.SessionBus.Own, value)
 			continue