diff --git a/packages/alt-ergo-lib/alt-ergo-lib.2.5.2/opam b/packages/alt-ergo-lib/alt-ergo-lib.2.5.2/opam
new file mode 100644
index 00000000000..be080554019
--- /dev/null
+++ b/packages/alt-ergo-lib/alt-ergo-lib.2.5.2/opam
@@ -0,0 +1,66 @@
+opam-version: "2.0"
+synopsis: "The Alt-Ergo SMT prover library"
+description: """
+This is the core library used in the Alt-Ergo SMT solver.
+
+Alt-Ergo is an automatic theorem prover of mathematical formulas. It was developed at LRI, and is now maintained at OCamlPro.
+
+See more details on http://alt-ergo.ocamlpro.com/"""
+maintainer: ["Alt-Ergo developers"]
+authors: ["Alt-Ergo developers"]
+homepage: "https://alt-ergo.ocamlpro.com/"
+doc: "https://ocamlpro.github.io/alt-ergo"
+bug-reports: "https://github.com/OCamlPro/alt-ergo/issues"
+depends: [
+  "ocaml" {>= "4.08.0"}
+  "dune" {>= "3.0"}
+  "dune-build-info"
+  "dolmen" {>= "0.9"}
+  "dolmen_type" {>= "0.9"}
+  "dolmen_loop" {>= "0.9"}
+  "ocplib-simplex" {>= "0.5"}
+  "zarith" {>= "1.11"}
+  "seq"
+  "fmt" {>= "0.9.0"}
+  "stdlib-shims"
+  "ppx_blob" {>= "0.7.2"}
+  "camlzip" {>= "1.07"}
+  "odoc" {with-doc}
+]
+conflicts: [
+  "ppxlib" {< "0.30.0"}
+  "result" {< "1.5"}
+]
+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/OCamlPro/alt-ergo.git"
+# This part comes from the template. Please edit alt-ergo-lib.opam.template
+# and not alt-ergo-lib.opam which is generated by dune
+tags: "org:OCamlPro"
+
+license: [
+  "LicenseRef-OCamlpro-Non-Commercial"
+  "Apache-2.0"
+]
+url {
+  src: "https://github.com/OCamlPro/alt-ergo/releases/download/v2.5.2/alt-ergo-2.5.2.tbz"
+  checksum: [
+    "sha256=f460c17011f8f6c85e3b9023983b339cc11bc34252ae748e708211378d3f6895"
+    "sha512=cc4707f22596838dd242dc2e42b5d744dd0c44f5283c0a36074761d5b8c91e6f46fed2aebb5f6a96d50f94e5da2b74cd18447574668db255a19a6fb0cda9bbb7"
+  ]
+}
+x-commit-hash: "e14d9b7c777f8fb15749489d292a189e3d71a8e7"
diff --git a/packages/alt-ergo-parsers/alt-ergo-parsers.2.5.2/opam b/packages/alt-ergo-parsers/alt-ergo-parsers.2.5.2/opam
new file mode 100644
index 00000000000..ff2c501d217
--- /dev/null
+++ b/packages/alt-ergo-parsers/alt-ergo-parsers.2.5.2/opam
@@ -0,0 +1,55 @@
+opam-version: "2.0"
+synopsis: "The Alt-Ergo SMT prover parser library"
+description: """
+This is the parser library used in the Alt-Ergo SMT solver.
+
+Alt-Ergo is an automatic theorem prover of mathematical formulas. It was developed at LRI, and is now maintained at OCamlPro.
+
+See more details on http://alt-ergo.ocamlpro.com/"""
+maintainer: ["Alt-Ergo developers"]
+authors: ["Alt-Ergo developers"]
+homepage: "https://alt-ergo.ocamlpro.com/"
+doc: "https://ocamlpro.github.io/alt-ergo"
+bug-reports: "https://github.com/OCamlPro/alt-ergo/issues"
+depends: [
+  "ocaml" {>= "4.08.0"}
+  "dune" {>= "3.0"}
+  "alt-ergo-lib" {= version}
+  "psmt2-frontend" {>= "0.4"}
+  "menhir"
+  "stdlib-shims"
+  "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/OCamlPro/alt-ergo.git"
+# This part comes from the template. Please edit alt-ergo-parsers.opam.template
+# and not alt-ergo-parsers.opam which is generated by dune
+tags: "org:OCamlPro"
+
+license: [
+  "LicenseRef-OCamlpro-Non-Commercial"
+  "Apache-2.0"
+]
+url {
+  src: "https://github.com/OCamlPro/alt-ergo/releases/download/v2.5.2/alt-ergo-2.5.2.tbz"
+  checksum: [
+    "sha256=f460c17011f8f6c85e3b9023983b339cc11bc34252ae748e708211378d3f6895"
+    "sha512=cc4707f22596838dd242dc2e42b5d744dd0c44f5283c0a36074761d5b8c91e6f46fed2aebb5f6a96d50f94e5da2b74cd18447574668db255a19a6fb0cda9bbb7"
+  ]
+}
+x-commit-hash: "e14d9b7c777f8fb15749489d292a189e3d71a8e7"
diff --git a/packages/alt-ergo-plugin-ab-why3/alt-ergo-plugin-ab-why3.2.5.2/opam b/packages/alt-ergo-plugin-ab-why3/alt-ergo-plugin-ab-why3.2.5.2/opam
new file mode 100644
index 00000000000..4390d312460
--- /dev/null
+++ b/packages/alt-ergo-plugin-ab-why3/alt-ergo-plugin-ab-why3.2.5.2/opam
@@ -0,0 +1,45 @@
+opam-version: "2.0"
+synopsis: "An experimental Why3 frontend for Alt-Ergo"
+description: """
+An experimental front-end that parses a subset of Why3's logic. More
+precisely, this front-end targets proof obligations generated by the
+Atelier-B framework in Why3 format. It should be used with a prelude
+defining the B Set theory."""
+maintainer: ["Alt-Ergo developers"]
+authors: ["Alt-Ergo developers"]
+license: "LGPL-2.1-only"
+homepage: "https://alt-ergo.ocamlpro.com/"
+doc: "https://ocamlpro.github.io/alt-ergo"
+bug-reports: "https://github.com/OCamlPro/alt-ergo/issues"
+depends: [
+  "dune" {>= "3.0"}
+  "alt-ergo" {= version}
+  "alt-ergo-lib" {= version}
+  "alt-ergo-parsers" {= 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/OCamlPro/alt-ergo.git"
+url {
+  src: "https://github.com/OCamlPro/alt-ergo/releases/download/v2.5.2/alt-ergo-2.5.2.tbz"
+  checksum: [
+    "sha256=f460c17011f8f6c85e3b9023983b339cc11bc34252ae748e708211378d3f6895"
+    "sha512=cc4707f22596838dd242dc2e42b5d744dd0c44f5283c0a36074761d5b8c91e6f46fed2aebb5f6a96d50f94e5da2b74cd18447574668db255a19a6fb0cda9bbb7"
+  ]
+}
+x-commit-hash: "e14d9b7c777f8fb15749489d292a189e3d71a8e7"
diff --git a/packages/alt-ergo/alt-ergo.2.5.2/opam b/packages/alt-ergo/alt-ergo.2.5.2/opam
new file mode 100644
index 00000000000..40a02dc5b8a
--- /dev/null
+++ b/packages/alt-ergo/alt-ergo.2.5.2/opam
@@ -0,0 +1,54 @@
+opam-version: "2.0"
+synopsis: "The Alt-Ergo SMT prover"
+description: """
+Alt-Ergo is an automatic theorem prover of mathematical formulas. It was developed at LRI, and is now maintained at OCamlPro.
+
+See more details on https://alt-ergo.ocamlpro.com/"""
+maintainer: ["Alt-Ergo developers"]
+authors: ["Alt-Ergo developers"]
+homepage: "https://alt-ergo.ocamlpro.com/"
+doc: "https://ocamlpro.github.io/alt-ergo"
+bug-reports: "https://github.com/OCamlPro/alt-ergo/issues"
+depends: [
+  "ocaml" {>= "4.08.0"}
+  "dune" {>= "3.0"}
+  "alt-ergo-lib" {= version}
+  "alt-ergo-parsers" {= version}
+  "menhir"
+  "dune-site"
+  "cmdliner" {>= "1.1.0"}
+  "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/OCamlPro/alt-ergo.git"
+# This part comes from the template. Please edit alt-ergo.opam.template
+# and not alt-ergo.opam which is generated by dune
+tags: "org:OCamlPro"
+
+license: [
+  "LicenseRef-OCamlpro-Non-Commercial"
+  "Apache-2.0"
+]
+url {
+  src: "https://github.com/OCamlPro/alt-ergo/releases/download/v2.5.2/alt-ergo-2.5.2.tbz"
+  checksum: [
+    "sha256=f460c17011f8f6c85e3b9023983b339cc11bc34252ae748e708211378d3f6895"
+    "sha512=cc4707f22596838dd242dc2e42b5d744dd0c44f5283c0a36074761d5b8c91e6f46fed2aebb5f6a96d50f94e5da2b74cd18447574668db255a19a6fb0cda9bbb7"
+  ]
+}
+x-commit-hash: "e14d9b7c777f8fb15749489d292a189e3d71a8e7"