add schema version

default.nix

@@ -7,6 +7,7 @@ let
       astore = self.callCabal2nix "astore" sources.json2sql { };
       autotypes = self.callCabal2nix "autotypes" ./autotypes { };
       backend = self.callCabal2nix "backend" ./backend { };
+      common = self.callCabal2nix "common" ./common { };
       frontend = self.callCabal2nix "frontend" ./frontend { };
       websockets = pkgs.haskell.lib.doJailbreak super.websockets;
     };
@@ -14,6 +15,7 @@ let
 
   jsHaskellPackages = pkgs.pkgsCross.ghcjs.haskell.packages.ghc98.override {
     overrides = self: super: {
+      common = self.callCabal2nix "common" ./common { };
       frontend = self.callCabal2nix "frontend" ./frontend { };
     };
   };
@@ -25,6 +27,7 @@ rec {
     packages = _: [
       haskellPackages.autotypes
       haskellPackages.backend
+      haskellPackages.common
       haskellPackages.frontend
     ];
     buildInputs = [