diff --git a/packages/domain-name/domain-name.0.3.1/opam b/packages/domain-name/domain-name.0.3.1/opam
new file mode 100644
index 000000000000..2790e7de2362
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+++ b/packages/domain-name/domain-name.0.3.1/opam
@@ -0,0 +1,36 @@
+opam-version: "2.0"
+maintainer: "Hannes Mehnert <hannes@mehnert.org>"
+authors: "Hannes Mehnert <hannes@mehnert.org>"
+license: "ISC"
+homepage: "https://github.com/hannesm/domain-name"
+doc: "https://hannesm.github.io/domain-name/doc"
+bug-reports: "https://github.com/hannesm/domain-name/issues"
+depends: [
+  "ocaml" {>= "4.04.2"}
+  "dune"
+  "alcotest" {with-test}
+]
+build: [
+  ["dune" "subst"] {dev}
+  ["dune" "build" "-p" name "-j" jobs]
+  ["dune" "runtest" "-p" name "-j" jobs] {with-test}
+]
+dev-repo: "git+https://github.com/hannesm/domain-name.git"
+synopsis: "RFC 1035 Internet domain names"
+description: """
+A domain name is a sequence of labels separated by dots, such as `foo.example`.
+Each label may contain any bytes. The length of each label may not exceed 63
+charactes.  The total length of a domain name is limited to 253 (byte
+representation is 255), but other protocols (such as SMTP) may apply even
+smaller limits.  A domain name label is case preserving, comparison is done in a
+case insensitive manner.
+"""
+url {
+  src:
+    "https://github.com/hannesm/domain-name/releases/download/v0.3.1/domain-name-v0.3.1.tbz"
+  checksum: [
+    "sha256=73d5d4b64fd7b5350d7d886edc81452b571361ee1997a86cfc0c90a0c0e8f64a"
+    "sha512=e4be7c094c3d58cbf4bc627596a7eacbe715cb68d5920f8662661b0c76a3c4d563f2b478a49e98c932f7313ed3efe6a432513580a372f14bca2cfd5f8a76f61d"
+  ]
+}
+x-commit-hash: "4d50b4ee43a8611bade7331a2417605a313d6499"