diff --git a/pkgs/development/ocaml-modules/janestreet/0.15.nix b/pkgs/development/ocaml-modules/janestreet/0.15.nix
index 7433c116b68f..bf61ae1d939c 100644
--- a/pkgs/development/ocaml-modules/janestreet/0.15.nix
+++ b/pkgs/development/ocaml-modules/janestreet/0.15.nix
@@ -254,6 +254,15 @@ with self;
     propagatedBuildInputs = [ async_websocket cohttp-async ppx_jane uri-sexp ];
   };
 
+  cohttp_static_handler = janePackage {
+    duneVersion = "3";
+    pname = "cohttp_static_handler";
+    version = "0.15.0";
+    hash = "sha256-ENaH8ChvjeMc9WeNIhkeNBB7YK9vB4lw95o6FFZI1ys=";
+    meta.description = "A library for easily creating a cohttp handler for static files";
+    propagatedBuildInputs = [ cohttp-async ];
+  };
+
   core = janePackage {
     pname = "core";
     version = "0.15.1";
diff --git a/pkgs/development/ocaml-modules/magic-trace/default.nix b/pkgs/development/ocaml-modules/magic-trace/default.nix
new file mode 100644
index 000000000000..1f1417f67275
--- /dev/null
+++ b/pkgs/development/ocaml-modules/magic-trace/default.nix
@@ -0,0 +1,27 @@
+{ lib, fetchFromGitHub, buildDunePackage, async, cohttp_static_handler
+, core_unix, owee, ppx_jane, shell }:
+
+buildDunePackage rec {
+  pname = "magic-trace";
+  version = "1.1.0";
+
+  minimalOCamlVersion = "4.12";
+  duneVersion = "3";
+
+  src = fetchFromGitHub {
+    owner = "janestreet";
+    repo = "magic-trace";
+    rev = "v${version}";
+    sha256 = "sha256-615AOkrbQI6vRosA5Kz3Epipe9f9+Gs9+g3bVl5gzBY=";
+  };
+
+  buildInputs = [ async cohttp_static_handler core_unix owee ppx_jane shell ];
+
+  meta = with lib; {
+    description =
+      "Collects and displays high-resolution traces of what a process is doing";
+    license = licenses.mit;
+    maintainers = [ maintainers.alizter ];
+    homepage = "https://github.com/janestreet/magic-trace";
+  };
+}
diff --git a/pkgs/development/ocaml-modules/owee/default.nix b/pkgs/development/ocaml-modules/owee/default.nix
index 7b15437a7ed2..3b8e6f58cfb2 100644
--- a/pkgs/development/ocaml-modules/owee/default.nix
+++ b/pkgs/development/ocaml-modules/owee/default.nix
@@ -2,19 +2,20 @@
 
 buildDunePackage rec {
   minimalOCamlVersion = "4.06";
-  useDune2 = true;
+  duneVersion = "2";
   pname = "owee";
-  version = "0.4";
+  version = "0.6";
 
   src = fetchurl {
-    url = "https://github.com/let-def/owee/releases/download/v${version}/owee-${version}.tbz";
-    sha256 = "sha256:055bi0yfdki1pqagbhrwmfvigyawjgsmqw04zhpp6hds8513qzvb";
+    url =
+      "https://github.com/let-def/owee/releases/download/v${version}/owee-${version}.tbz";
+    sha256 = "sha256-GwXV5t4GYbDiGwyvQyW8NZoYvn4qXlLnjX331Bj1wjM=";
   };
 
-  meta = {
+  meta = with lib; {
     description = "An experimental OCaml library to work with DWARF format";
     homepage = "https://github.com/let-def/owee/";
-    license = lib.licenses.mit;
-    maintainers = [ lib.maintainers.vbgl ];
+    license = licenses.mit;
+    maintainers = with maintainers; [ vbgl alizter ];
   };
 }
diff --git a/pkgs/development/ocaml-modules/spacetime_lib/default.nix b/pkgs/development/ocaml-modules/spacetime_lib/default.nix
index 442d06e4f698..7e2e4002c1ea 100644
--- a/pkgs/development/ocaml-modules/spacetime_lib/default.nix
+++ b/pkgs/development/ocaml-modules/spacetime_lib/default.nix
@@ -6,8 +6,7 @@ lib.throwIfNot (lib.versionAtLeast "4.12" ocaml.version)
 buildDunePackage rec {
   pname = "spacetime_lib";
   version = "0.3.0";
-
-  useDune2 = true;
+  duneVersion = "2";
 
   src = fetchFromGitHub {
     owner = "lpw25";
@@ -16,6 +15,8 @@ buildDunePackage rec {
     sha256 = "0biisgbycr5v3nm5jp8i0h6vq76vzasdjkcgh8yr7fhxc81jgv3p";
   };
 
+  patches = [ ./spacetime.diff ];
+
   propagatedBuildInputs = [ owee ];
 
   preConfigure = ''
diff --git a/pkgs/development/ocaml-modules/spacetime_lib/spacetime.diff b/pkgs/development/ocaml-modules/spacetime_lib/spacetime.diff
new file mode 100644
index 000000000000..baad34ce08b5
--- /dev/null
+++ b/pkgs/development/ocaml-modules/spacetime_lib/spacetime.diff
@@ -0,0 +1,14 @@
+diff --git a/src/elf_locations.ml b/src/elf_locations.ml
+index a08b359..0db9274 100644
+--- a/src/elf_locations.ml
++++ b/src/elf_locations.ml
+@@ -37,7 +37,8 @@ let resolve_from_dwarf t ~program_counter =
+     | Some section ->
+       let body = Owee_buf.cursor (Owee_elf.section_body t.map section) in
+       let rec aux () =
+-        match Owee_debug_line.read_chunk body with
++        let pointers_to_other_sections = Owee_elf.debug_line_pointers t.map t.sections in
++        match Owee_debug_line.read_chunk body ~pointers_to_other_sections with
+         | None -> ()
+         | Some (header, chunk) ->
+           (* CR-soon mshinwell: fix owee .mli to note that [state] is
diff --git a/pkgs/top-level/ocaml-packages.nix b/pkgs/top-level/ocaml-packages.nix
index d1e599d8970f..3f8667af9ae7 100644
--- a/pkgs/top-level/ocaml-packages.nix
+++ b/pkgs/top-level/ocaml-packages.nix
@@ -895,6 +895,8 @@ let
 
     magic-mime = callPackage ../development/ocaml-modules/magic-mime { };
 
+    magic-trace = callPackage ../development/ocaml-modules/magic-trace { };
+
     mariadb = callPackage ../development/ocaml-modules/mariadb {
       inherit (pkgs) mariadb;
     };