diff --git a/appvm.go b/appvm.go
index eb3b5e6..750897e 100644
--- a/appvm.go
+++ b/appvm.go
@@ -372,7 +372,12 @@ func main() {
 
 	os.MkdirAll(configDir+"/nix", 0700)
 
-	err := ioutil.WriteFile(configDir+"/nix/base.nix", base_nix, 0644)
+	err := writeBuiltinApps(configDir + "/nix")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	err = ioutil.WriteFile(configDir+"/nix/base.nix", base_nix, 0644)
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/nix/chromium.nix b/builtin.go
similarity index 67%
rename from nix/chromium.nix
rename to builtin.go
index bfac831..0b6b99e 100644
--- a/nix/chromium.nix
+++ b/builtin.go
@@ -1,3 +1,19 @@
+package main
+
+import (
+	"io/ioutil"
+)
+
+// Builtin VMs
+
+type app struct {
+	Name string
+	Nix  []byte
+}
+
+var builtin_chromium_nix = app{
+	Name: "chromium",
+	Nix: []byte(`
 {pkgs, ...}:
 {
   imports = [
@@ -19,3 +35,18 @@
   environment.systemPackages = [ pkgs.chromium ];
   services.xserver.displayManager.sessionCommands = "while [ 1 ]; do ${pkgs.chromium}/bin/chromium; done &";
 }
+`),
+}
+
+func writeBuiltinApps(path string) (err error) {
+	for _, f := range []app{
+		builtin_chromium_nix,
+	} {
+		err = ioutil.WriteFile(configDir+"/nix/"+f.Name+".nix", f.Nix, 0644)
+		if err != nil {
+			return
+		}
+	}
+
+	return
+}