diff --git a/packages/opatch/opatch.3.1.0/opam b/packages/opatch/opatch.3.1.0/opam
new file mode 100644
index 000000000000..7dbf70f0f599
--- /dev/null
+++ b/packages/opatch/opatch.3.1.0/opam
@@ -0,0 +1,41 @@
+opam-version: "2.0"
+synopsis: "Pure OCaml command-line tool to apply a patch"
+description:
+  "Command-line tool to apply a unified diff or git-diff to a directory"
+maintainer: ["Samuel Hym <samuel@tarides.com>"]
+authors: [
+  "Kate Deplaix <kit-ty-kate@exn.st>" "Samuel Hym <samuel@tarides.com>"
+]
+license: "ISC"
+homepage: "https://github.com/hannesm/patch"
+bug-reports: "https://github.com/hannesm/patch/issues"
+depends: [
+  "dune" {>= "3.0"}
+  "ocaml" {>= "4.14"}
+  "patch" {= version}
+  "odoc" {with-doc}
+]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://github.com/hannesm/patch.git"
+x-maintenance-intent: [ "(latest)" ]
+url {
+  src:
+    "https://github.com/hannesm/patch/releases/download/v3.1.0/patch-3.1.0.tbz"
+  checksum: [
+    "sha256=63d9e820295dd257f32efbfde171f1bc940c0c83aae1ed5a501bb57970d52294"
+    "sha512=2ac8671fc3ff5e615331f2c363c7fba819352f45e963a37acfdabfc930689c3561fd3700e49295d8758cd354fa6ae63ae897da868802ed1d2b92e301059c34c3"
+  ]
+}
+x-commit-hash: "59a318563d745e63fc69f3d58a8a8ff302e91c4b"
diff --git a/packages/patch/patch.3.1.0/opam b/packages/patch/patch.3.1.0/opam
new file mode 100644
index 000000000000..81aa6feff0a3
--- /dev/null
+++ b/packages/patch/patch.3.1.0/opam
@@ -0,0 +1,38 @@
+opam-version: "2.0"
+maintainer: "Hannes Mehnert <hannes@mehnert.org>"
+authors: [
+  "Hannes Mehnert <hannes@mehnert.org>"
+  "Kate <kit-ty-kate@exn.st>"
+]
+homepage: "https://github.com/hannesm/patch"
+doc: "https://hannesm.github.io/patch/"
+dev-repo: "git+https://github.com/hannesm/patch.git"
+bug-reports: "https://github.com/hannesm/patch/issues"
+license: "ISC"
+
+depends: [
+  "ocaml" {>= "4.08"}
+  "dune" {>= "3.0"}
+  "alcotest" {with-test & >= "1.7.0"}
+  "crowbar" {with-test}
+]
+build: [
+  ["dune" "subst"] {dev}
+  ["dune" "build" "-p" name "-j" jobs]
+  ["dune" "runtest" "-p" name "-j" jobs] {with-test}
+]
+synopsis: "Patch library purely in OCaml"
+description: """
+This is a library which parses unified diff and git diff output, and can
+apply a patch in memory.
+"""
+x-maintenance-intent: [ "(latest)" ]
+url {
+  src:
+    "https://github.com/hannesm/patch/releases/download/v3.1.0/patch-3.1.0.tbz"
+  checksum: [
+    "sha256=63d9e820295dd257f32efbfde171f1bc940c0c83aae1ed5a501bb57970d52294"
+    "sha512=2ac8671fc3ff5e615331f2c363c7fba819352f45e963a37acfdabfc930689c3561fd3700e49295d8758cd354fa6ae63ae897da868802ed1d2b92e301059c34c3"
+  ]
+}
+x-commit-hash: "59a318563d745e63fc69f3d58a8a8ff302e91c4b"