diff --git a/pkgs/development/ocaml-modules/yamlx/default.nix b/pkgs/development/ocaml-modules/yamlx/default.nix
new file mode 100644
index 000000000000..152c879c8ac7
--- /dev/null
+++ b/pkgs/development/ocaml-modules/yamlx/default.nix
@@ -0,0 +1,31 @@
+{
+  lib,
+  buildDunePackage,
+  fetchurl,
+  ppx_deriving,
+  testo,
+}:
+
+buildDunePackage (finalAttrs: {
+  pname = "yamlx";
+  version = "0.1.0";
+
+  src = fetchurl {
+    url = "https://github.com/mjambon/yamlx/releases/download/${finalAttrs.version}/yamlx-${finalAttrs.version}.tbz";
+    hash = "sha256-Ihar37R1dUFMXSgNGEJu5z6ysFMcrg1Hd74hNLletwE=";
+  };
+
+  propagatedBuildInputs = [ ppx_deriving ];
+
+  doCheck = true;
+  checkInputs = [ testo ];
+
+  minimalOCamlVersion = "4.14";
+
+  meta = {
+    description = "Pure-OCaml YAML 1.2 parser with a lossless, comment-preserving AST";
+    maintainers = [ lib.maintainers.vbgl ];
+    license = lib.licenses.agpl3Only;
+    homepage = "https://github.com/mjambon/yamlx";
+  };
+})
diff --git a/pkgs/top-level/ocaml-packages.nix b/pkgs/top-level/ocaml-packages.nix
index 85a8b5df2a14..1309bbb7de0a 100644
--- a/pkgs/top-level/ocaml-packages.nix
+++ b/pkgs/top-level/ocaml-packages.nix
@@ -2285,6 +2285,8 @@ let
 
         yaml-sexp = callPackage ../development/ocaml-modules/yaml/yaml-sexp.nix { };
 
+        yamlx = callPackage ../development/ocaml-modules/yamlx { };
+
         yojson = callPackage ../development/ocaml-modules/yojson { };
 
         yojson_2 = yojson.overrideAttrs (_: {