1 files changed, 24 insertions, 0 deletions
diff --git a/third_party/lisp/closer-mop.nix b/third_party/lisp/closer-mop.nix
new file mode 100644
index 000000000000..21fb3ba14bef
--- /dev/null
+++ b/third_party/lisp/closer-mop.nix
@@ -0,0 +1,24 @@
+# Closer to MOP is a compatibility layer that rectifies many of the
+# absent or incorrect CLOS MOP features across a broad range of Common
+# Lisp implementations
+{ depot, pkgs, ... }:
+
+let src = pkgs.fetchFromGitHub {
+  owner = "pcostanza";
+  repo = "closer-mop";
+  rev = "8ec9577029b08ade5978236121c9ac276f78d8be"; # 2021-07-30
+  sha256 = "0dm8xsa3hzpxjd7x248pbzd8blw01a8ls7spalzgbg1g7vbn6zg5";
+};
+in depot.nix.buildLisp.library {
+  name = "closer-mop";
+
+  srcs = [
+    "${src}/closer-mop-packages.lisp"
+    "${src}/closer-mop-shared.lisp"
+    {
+      sbcl = "${src}/closer-sbcl.lisp";
+      ecl = "${src}/closer-ecl.lisp";
+      ccl = "${src}/closer-clozure.lisp";
+    }
+  ];
+}