diff --git a/packages/malfunction/malfunction.0.6/opam b/packages/malfunction/malfunction.0.6/opam
new file mode 100644
index 00000000000..692a28f54be
--- /dev/null
+++ b/packages/malfunction/malfunction.0.6/opam
@@ -0,0 +1,33 @@
+opam-version: "2.0"
+maintainer: "sdolan@janestreet.com"
+authors: ["Stephen Dolan"]
+homepage: "https://github.com/stedolan/malfunction"
+bug-reports: "https://github.com/stedolan/malfunction/issues"
+dev-repo: "git+https://github.com/stedolan/malfunction.git"
+license: "LGPL-2.0-or-later"
+build: [
+  [ "dune" "build" "-p" name "-j" jobs ]
+  [ "dune" "runtest" "-p" name "-j" jobs ] {with-test}
+]
+conflicts: [ "ocaml-option-bytecode-only" ]
+depends: [
+  "ocaml" {>= "4.08"}
+  "ocamlfind"
+  "dune" {>= "2.9.1"}
+  "cppo" {build}
+  "omd" {with-test & >= "2.0.0~"}
+  "zarith"
+]
+synopsis: "Compiler back-end for functional languages, based on OCaml"
+description: """
+Malfunction is a high-performance, low-level untyped program
+representation, designed as a target for compilers of functional
+programming languages."""
+url {
+  src:
+    "https://github.com/stedolan/malfunction/archive/refs/tags/v0.6.tar.gz"
+  checksum: [
+    "md5=d84601d743611a1a44413498a8b07076"
+    "sha512=f113b5cf34695a1f53f2270a0ede56bee619c5b987602760550bb41cf1c4f8d86b91e6c0a866c1aae7df812edc0f9b907822226a6337bc07ee6e16eda746f470"
+  ]
+}