diff --git a/flake.nix b/flake.nix
index 16a4bc0..ed75e52 100644
--- a/flake.nix
+++ b/flake.nix
@@ -17,8 +17,15 @@
     supportedSystems = ["aarch64-linux" "x86_64-linux" "x86_64-darwin"];
     forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
 
-    thesisType = ""; # ms, bc
-    throw "Set thesis type!"
+    # ms, bc
+    thesis = "";
+
+    checkThesisType = {type}:
+      if builtins.stringLength type == 0
+      then "unknown"
+      else type;
+    thesisType = checkThesisType {type = thesis;};
+
     documentName = "thesis";
     pname = thesisType + "_" + documentName;
     version = "0.0.1";