diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index c30a2f336fe..477ce167f35 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -174,11 +174,13 @@ jobs:
         if: steps.cache-opam.outputs.cache-hit != 'true'
         run: |
           set -ex
+          opam --version
           opam init # --disable-sandboxing
-          opam update
-          opam switch create ${{ matrix.ocaml }}
-          opam pin add haxe . --no-action
-          opam install haxe --deps-only --assume-depexts
+          opam switch create ${{ matrix.ocaml }} --locked --assume-depexts
+          # opam update
+          # opam switch create ${{ matrix.ocaml }}
+          # opam pin add haxe . --no-action
+          # opam install haxe --deps-only --assume-depexts
           opam list
           ocamlopt -v
 
diff --git a/haxe.opam b/haxe.opam
index e45a4b8dc58..2498d72cd33 100644
--- a/haxe.opam
+++ b/haxe.opam
@@ -1,4 +1,4 @@
-opam-version: "2.1"
+opam-version: "2.0"
 name: "haxe"
 version: "4.3.0"
 synopsis: "Multi-target universal programming language"
@@ -20,7 +20,6 @@ install: [make "install" "INSTALL_DIR=%{prefix}%"]
 remove: [make "uninstall" "INSTALL_DIR=%{prefix}%"]
 depends: [
   ("ocaml" {>= "5.0"} & ("camlp5" {build}))
-    | ("ocaml" {>= "4.08" & < "5.0"} & ("camlp5" {build & = "8.00.03"}))
   "ocamlfind" {build}
   "dune" {>= "1.11" & < "3.16"}
   "sedlex" {>= "2.0"}
@@ -31,7 +30,7 @@ depends: [
   "conf-libpcre2-8"
   "conf-zlib"
   "conf-neko"
-  "luv" {= "0.5.12"}
+  "luv" {>= "0.5.12" & < "0.6"}
   "ipaddr"
   "terminal_size"
 ]
diff --git a/haxe.opam.locked b/haxe.opam.locked
new file mode 100644
index 00000000000..894506fa18b
--- /dev/null
+++ b/haxe.opam.locked
@@ -0,0 +1,82 @@
+opam-version: "2.0"
+name: "haxe"
+version: "4.3.0"
+synopsis: "Multi-target universal programming language"
+description: """\
+Haxe is an open source toolkit based on a modern,
+high level, static-typed programming language, a cross-compiler,
+a complete cross-platform standard library and ways to access each
+platform's native capabilities."""
+maintainer: [
+  "Haxe Foundation <contact@haxe.org>" "Andy Li <andy@onthewings.net>"
+]
+authors: "Haxe Foundation <contact@haxe.org>"
+license: ["GPL2+" "MIT"]
+homepage: "https://haxe.org/"
+bug-reports: "https://github.com/HaxeFoundation/haxe/issues"
+depends: [
+  "astring" {= "0.8.5"}
+  "base-bigarray" {= "base"}
+  "base-domains" {= "base"}
+  "base-nnp" {= "base"}
+  "base-threads" {= "base"}
+  "base-unix" {= "base"}
+  "bigarray-compat" {= "1.1.0"}
+  "bos" {= "0.2.1"}
+  "camlp-streams" {= "5.0.1"}
+  "camlp5" {= "8.03.00"}
+  "camlp5-buildscripts" {= "0.03"}
+  "cmdliner" {= "1.3.0"}
+  "conf-bash" {= "1"}
+  "conf-libpcre2-8" {= "1"}
+  "conf-m4" {= "1"}
+  "conf-neko" {= "1"}
+  "conf-perl" {= "2"}
+  "conf-pkg-config" {= "3"}
+  "conf-which" {= "1"}
+  "conf-zlib" {= "1"}
+  "cppo" {= "1.6.9"}
+  "csexp" {= "1.5.2"}
+  "ctypes" {= "0.22.0"}
+  "domain-name" {= "0.4.0"}
+  "dune" {= "3.16.0"}
+  "dune-configurator" {= "3.16.0"}
+  "extlib" {= "1.7.9"}
+  "fmt" {= "0.9.0"}
+  "fpath" {= "0.7.3"}
+  "gen" {= "1.1"}
+  "host-arch-x86_64" {= "1"}
+  "host-system-other" {= "1"}
+  "integers" {= "0.7.0"}
+  "ipaddr" {= "5.6.0"}
+  "logs" {= "0.7.0"}
+  "luv" {= "0.5.13"}
+  "macaddr" {= "5.6.0"}
+  "not-ocamlfind" {= "0.13"}
+  "ocaml" {= "5.1.0"}
+  "ocaml-base-compiler" {= "5.1.0"}
+  "ocaml-compiler-libs" {= "v0.12.4"}
+  "ocaml-config" {= "3"}
+  "ocaml-options-vanilla" {= "1"}
+  "ocamlbuild" {= "0.14.3"}
+  "ocamlfind" {= "1.9.6"}
+  "ocamlgraph" {= "2.1.0"}
+  "ppx_derivers" {= "1.2.1"}
+  "ppxlib" {= "0.32.1"}
+  "re" {= "1.11.0"}
+  "rresult" {= "0.7.0"}
+  "sedlex" {= "3.2"}
+  "seq" {= "base"}
+  "sexplib0" {= "v0.17.0"}
+  "sha" {= "1.15.4"}
+  "stdlib-shims" {= "0.3.0"}
+  "topkg" {= "1.0.7"}
+  "xml-light" {= "2.5"}
+]
+build: make
+install: [make "install" "INSTALL_DIR=%{prefix}%"]
+remove: [make "uninstall" "INSTALL_DIR=%{prefix}%"]
+dev-repo: "git+https://github.com/HaxeFoundation/haxe.git"
+url {
+  src: "git+file:///git/haxe#ocaml5-compat"
+}