diff --git a/pkgs/by-name/se/seppo/package.nix b/pkgs/by-name/se/seppo/package.nix
index 3121d2274cc9..0c5488c639ff 100644
--- a/pkgs/by-name/se/seppo/package.nix
+++ b/pkgs/by-name/se/seppo/package.nix
@@ -12,14 +12,14 @@ in
 
 ocamlPackages.buildDunePackage {
   pname = "seppo";
-  version = "0-unstable-2025-06-03";
+  version = "0-unstable-2025-08-07";
 
   src = fetchFromGitea {
     domain = "codeberg.org";
     owner = "seppo";
     repo = "seppo";
-    rev = "33ae3e9f61d596fb91d3ab1a91fc26ae80981a93";
-    hash = "sha256-tOIIfYBLcZqQzoPxAVkE8RGX0sugUmDGpxIhIZ5Wy+w=";
+    rev = "d927311cae64883fe2b88f5a1c7e17c8cc525bad";
+    hash = "sha256-Lb2w0mRNNamCltAwdxOyAYh02wkN7yKJGBzqBIPKE8k=";
   };
 
   # Provide git sha to avoid git dependency
diff --git a/pkgs/development/ocaml-modules/domain-name/default.nix b/pkgs/development/ocaml-modules/domain-name/default.nix
index 2e1682076efe..279641b3d67f 100644
--- a/pkgs/development/ocaml-modules/domain-name/default.nix
+++ b/pkgs/development/ocaml-modules/domain-name/default.nix
@@ -1,31 +1,27 @@
 {
   lib,
   buildDunePackage,
-  ocaml,
   fetchurl,
   alcotest,
 }:
 
-buildDunePackage rec {
+buildDunePackage (finalAttrs: {
   pname = "domain-name";
-  version = "0.4.1";
+  version = "0.5.0";
 
   src = fetchurl {
-    url = "https://github.com/hannesm/domain-name/releases/download/v${version}/domain-name-${version}.tbz";
-    sha256 = "sha256-Hboy81p81cyBh9IeLMIaC2Z6ZFRHoO7+V6/jyiW8RWY=";
+    url = "https://github.com/hannesm/domain-name/releases/download/v${finalAttrs.version}/domain-name-${finalAttrs.version}.tbz";
+    hash = "sha256-nseuLCJ3LBULhM+j8h2b8l+uFKeW8x4g31LYb0ZJnYk=";
   };
 
-  minimalOCamlVersion = "4.04";
-  duneVersion = "3";
-
+  doCheck = true;
   checkInputs = [ alcotest ];
 
-  doCheck = lib.versionAtLeast ocaml.version "4.08";
-
   meta = {
     homepage = "https://github.com/hannesm/domain-name";
+    changelog = "https://github.com/hannesm/domain-name/blob/v${finalAttrs.version}/CHANGES.md";
     description = "RFC 1035 Internet domain names";
     license = lib.licenses.isc;
     maintainers = [ lib.maintainers.vbgl ];
   };
-}
+})
diff --git a/pkgs/development/ocaml-modules/magic-trace/default.nix b/pkgs/development/ocaml-modules/magic-trace/default.nix
index 8bf19a921081..4debd6a5994c 100644
--- a/pkgs/development/ocaml-modules/magic-trace/default.nix
+++ b/pkgs/development/ocaml-modules/magic-trace/default.nix
@@ -18,7 +18,7 @@
   zstandard ? null,
 }:
 
-buildDunePackage rec {
+buildDunePackage (finalAttrs: {
   pname = "magic-trace";
   version = "1.2.4";
 
@@ -27,13 +27,14 @@ buildDunePackage rec {
   src = fetchFromGitHub {
     owner = "janestreet";
     repo = "magic-trace";
-    rev = "v${version}";
+    tag = "v${finalAttrs.version}";
     hash = "sha256-LkhnlOd5rI8cbOYbVqrkRJ2qTcRn3Zzl6GjQEdjBjVA=";
   };
 
   nativeBuildInputs = [
     ocaml-crunch
   ];
+
   buildInputs = [
     angstrom
     async
@@ -50,10 +51,12 @@ buildDunePackage rec {
     zstandard
   ];
 
-  meta = with lib; {
+  meta = {
     description = "Collects and displays high-resolution traces of what a process is doing";
-    license = licenses.mit;
-    maintainers = [ maintainers.alizter ];
+    license = lib.licenses.mit;
+    maintainers = [ lib.maintainers.alizter ];
     homepage = "https://github.com/janestreet/magic-trace";
+    platforms = lib.platforms.linux;
+    mainProgram = "magic-trace";
   };
-}
+})
diff --git a/pkgs/development/ocaml-modules/tls/eio.nix b/pkgs/development/ocaml-modules/tls/eio.nix
index ef32131a26b1..f04129b6d26b 100644
--- a/pkgs/development/ocaml-modules/tls/eio.nix
+++ b/pkgs/development/ocaml-modules/tls/eio.nix
@@ -17,6 +17,8 @@ buildDunePackage {
 
   minimalOCamlVersion = "5.0";
 
+  __darwinAllowLocalNetworking = true;
+
   doCheck = true;
   nativeCheckInputs = [
     mdx.bin