diff --git a/packages/tar-mirage.2.1.99~dev/opam b/packages/tar-mirage.2.1.99~dev/opam
new file mode 100644
index 0000000..1a773c4
--- /dev/null
+++ b/packages/tar-mirage.2.1.99~dev/opam
@@ -0,0 +1,50 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+synopsis: "Read and write tar format files via MirageOS interfaces"
+description: """
+tar is a simple library to read and write tar files with an emphasis on
+streaming.  This library is functorised over external OS dependencies
+to facilitate embedding within MirageOS.
+"""
+maintainer: ["dave@recoil.org"]
+authors: ["Dave Scott" "Thomas Gazagnaire" "David Allsopp" "Antonin Décimo"]
+license: "ISC"
+tags: ["org:xapi-project" "org:mirage"]
+homepage: "https://github.com/mirage/ocaml-tar"
+doc: "https://mirage.github.io/ocaml-tar/"
+bug-reports: "https://github.com/mirage/ocaml-tar/issues"
+depends: [
+  "dune" {>= "2.9"}
+  "ocaml" {>= "4.08.0"}
+  "cstruct" {>= "1.9.0"}
+  "lwt" {>= "5.6.0"}
+  "mirage-block" {>= "2.0.0"}
+  "mirage-kv" {>= "3.0.0" & < "5.0.0"}
+  "ptime"
+  "tar" {= version}
+  "mirage-block-unix" {with-test & >= "2.5.0"}
+  "ounit2" {with-test}
+  "ounit2-lwt" {with-test}
+  "tar-unix" {with-test & = version}
+  "odoc" {with-doc}
+]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "--promote-install-files=false"
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+  ["dune" "install" "-p" name "--create-install-files" name]
+]
+dev-repo: "git+https://github.com/mirage/ocaml-tar.git"
+url {
+  src: "git+https://github.com/hannesm/ocaml-tar.git#kv-rw"
+}
diff --git a/packages/tar.2.1.99~dev/opam b/packages/tar.2.1.99~dev/opam
new file mode 100644
index 0000000..7ff88b4
--- /dev/null
+++ b/packages/tar.2.1.99~dev/opam
@@ -0,0 +1,45 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+synopsis: "Decode and encode tar format files in pure OCaml"
+description: """
+tar is a simple library to read and write tar files with an emphasis on
+streaming.
+
+This is pure OCaml code, no C bindings.
+"""
+maintainer: ["dave@recoil.org"]
+authors: ["Dave Scott" "Thomas Gazagnaire" "David Allsopp" "Antonin Décimo"]
+license: "ISC"
+tags: ["org:xapi-project" "org:mirage"]
+homepage: "https://github.com/mirage/ocaml-tar"
+doc: "https://mirage.github.io/ocaml-tar/"
+bug-reports: "https://github.com/mirage/ocaml-tar/issues"
+depends: [
+  "dune" {>= "2.9"}
+  "camlp-streams"
+  "ocaml" {>= "4.08.0"}
+  "ppx_cstruct" {build & >= "3.6.0"}
+  "cstruct" {>= "6.0.0"}
+  "decompress" {>= "1.5.1"}
+  "odoc" {with-doc}
+]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "--promote-install-files=false"
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+  ["dune" "install" "-p" name "--create-install-files" name]
+]
+dev-repo: "git+https://github.com/mirage/ocaml-tar.git"
+url {
+  src: "git+https://github.com/hannesm/ocaml-tar.git#kv-rw"
+}