diff --git a/pkgs/by-name/fl/flow/package.nix b/pkgs/by-name/fl/flow/package.nix
index 281a2fb80862..04b73eae9f5c 100644
--- a/pkgs/by-name/fl/flow/package.nix
+++ b/pkgs/by-name/fl/flow/package.nix
@@ -8,7 +8,7 @@
 }:
 
 let
-  ocamlPackages = ocaml-ng.ocamlPackages.overrideScope (
+  ocamlPackages = ocaml-ng.ocamlPackages_5_3.overrideScope (
     self: super: {
       ppxlib = super.ppxlib.override { version = "0.34.0"; };
     }
diff --git a/pkgs/development/ocaml-modules/synchronizer/default.nix b/pkgs/development/ocaml-modules/synchronizer/default.nix
index 519c55ba9bdf..a3cb79b7467f 100644
--- a/pkgs/development/ocaml-modules/synchronizer/default.nix
+++ b/pkgs/development/ocaml-modules/synchronizer/default.nix
@@ -10,7 +10,7 @@ buildDunePackage (finalAttrs: {
   pname = "synchronizer";
   version = "0.2";
 
-  minimalOCamlVersion = "5.1";
+  minimalOCamlVersion = "5.2";
 
   src = fetchFromGitHub {
     owner = "OCamlPro";
diff --git a/pkgs/os-specific/linux/sgx/sdk/default.nix b/pkgs/os-specific/linux/sgx/sdk/default.nix
index 9da7360db581..108f411a52ef 100644
--- a/pkgs/os-specific/linux/sgx/sdk/default.nix
+++ b/pkgs/os-specific/linux/sgx/sdk/default.nix
@@ -12,7 +12,6 @@
   git,
   libtool,
   linkFarmFromDrvs,
-  ocaml,
   ocamlPackages,
   openssl,
   perl,
@@ -83,7 +82,7 @@ stdenv.mkDerivation rec {
     cmake
     file
     git
-    ocaml
+    ocamlPackages.ocaml
     ocamlPackages.ocamlbuild
     perl
     python3
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index b52fef4e05ad..b23692e44c5f 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -4541,6 +4541,10 @@ with pkgs;
   haxePackages = recurseIntoAttrs (callPackage ./haxe-packages.nix { });
   inherit (haxePackages) hxcpp;
 
+  heptagon = callPackage ../by-name/he/heptagon/package.nix {
+    ocamlPackages = ocaml-ng.ocamlPackages_5_3;
+  };
+
   dotnetPackages = recurseIntoAttrs (callPackage ./dotnet-packages.nix { });
 
   gopro-tool = callPackage ../by-name/go/gopro-tool/package.nix {
@@ -9460,7 +9464,9 @@ with pkgs;
 
   rfkill_udev = callPackage ../os-specific/linux/rfkill/udev.nix { };
 
-  sgx-sdk = callPackage ../os-specific/linux/sgx/sdk { };
+  sgx-sdk = callPackage ../os-specific/linux/sgx/sdk {
+    ocamlPackages = ocaml-ng.ocamlPackages_5_3;
+  };
 
   sgx-psw = callPackage ../os-specific/linux/sgx/psw {
     protobuf = protobuf_21;
diff --git a/pkgs/top-level/ocaml-packages.nix b/pkgs/top-level/ocaml-packages.nix
index 93228129e5f2..8542c13c2767 100644
--- a/pkgs/top-level/ocaml-packages.nix
+++ b/pkgs/top-level/ocaml-packages.nix
@@ -2357,7 +2357,7 @@ rec {
 
   ocamlPackages_latest = ocamlPackages_5_4;
 
-  ocamlPackages = ocamlPackages_5_3;
+  ocamlPackages = ocamlPackages_5_4;
 
   # We still have packages that rely on unsafe-string, which is deprecated in OCaml 4.06.0.
   # Below are aliases for porting them to the latest versions of the OCaml 4 series.