first failing test

default.nix

@@ -0,0 +1,49 @@
+{ stdenv
+, callPackage
+, fennel
+, fetchFromGitHub
+, fetchurl
+, lib
+, lua53Packages
+, lua5_3
+}:
+let pname = "rover";
+    lume = let lua = lua5_3; in lua53Packages.buildLuaPackage rec {
+      pname = "lume";
+      version = "1";
+      src = fetchFromGitHub {
+        repo = "lume"; owner = "rxi";
+        rev = "98847e7812cf28d3d64b289b03fad71dc704547d";
+        hash = "sha256-/u23EqgjjkU8FV9oXvMNXBkY8JAOJUhJAzXTSibJthU=";
+      };
+      buildPhase = ":";
+      installPhase = ''
+        mkdir -p "$out/share/lua/${lua.luaversion}"
+        cp lume.lua "$out/share/lua/${lua.luaversion}"
+      '';
+    };
+
+    lua = lua5_3.withPackages (ps: with ps; [
+      lgi
+      luafilesystem
+      luaposix
+      readline
+      lume
+    ]);
+    fennel_ = lua.pkgs.fennel;
+in stdenv.mkDerivation rec {
+  inherit pname;
+  fennel = fennel_;
+
+  version = "0.1";
+  src = lib.sources.cleanSource ./.;
+
+  buildInputs = [
+    lua
+    fennel
+  ];
+  nativeBuildInputs = [
+    lua
+  ];
+
+}

rover.fnl

@@ -0,0 +1,9 @@
+(local { : view } (require :fennel))
+
+(fn rover [x y direction]
+  {})
+
+(let [r (rover 0 0 :n)]
+  (match r
+    {:x 0 :y 0 :direction :n} true
+    _ (assert false (view r))))

shell.nix

@@ -0,0 +1,10 @@
+with import <nixpkgs> {} ;
+let p  = callPackage ./. {};
+in p.overrideAttrs(o: {
+  nativeBuildInputs = o.nativeBuildInputs ++ (with pkgs; [
+    socat
+    overmind
+    entr
+  ]);
+  JUST_HACKING = 1;
+})