diff --git a/eggs.nix b/eggs.nix
new file mode 100644
index 0000000..cd1f531
--- /dev/null
+++ b/eggs.nix
@@ -0,0 +1,18 @@
+{ pkgs, stdenv }:
+rec {
+  inherit (pkgs) eggDerivation fetchegg;
+
+  numbers = eggDerivation {
+    name = "numbers-4.6.3";
+
+    src = fetchegg {
+      name = "numbers";
+      version = "4.6.3";
+      sha256 = "0aczzpq6f31lk1919aiywknaci69m1apyx905m2ln2qw8zwmwibq";
+    };
+
+    buildInputs = [
+    ];
+  };
+}
+
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..bd2807e
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,17 @@
+{ nixpkgs ? <nixpkgs> }:
+let
+  pkgs = import (builtins.fetchTarball {
+    name = "nixos-unstable-2018-12-08";
+    url = https://github.com/nixos/nixpkgs/archive/e85c1f586807b5acd244df4c45a5130aa3f0734d.tar.gz;
+    sha256 = "1xy1qgam0i2fyqhaczw0qrx8yv3hgdh9jp47wmln5ljiixr5ic5n";
+    }) {};
+  stdenv = pkgs.stdenv;
+  eggs = import ./eggs.nix { inherit pkgs stdenv; };
+  idrisWithPkgs = pkgs.idrisPackages.with-packages (with pkgs.idrisPackages; [ contrib pruviloj ]);
+in
+with pkgs; stdenv.mkDerivation {
+  name = "blodwen-shell-extras";
+  buildInputs = [
+    gmp chez idrisWithPkgs chicken eggs.numbers bazel
+  ];
+}