diff --git a/lib/licenses.nix b/lib/licenses.nix
index 772985f9509d..bde2aaca2ee5 100644
--- a/lib/licenses.nix
+++ b/lib/licenses.nix
@@ -240,6 +240,11 @@ in mkLicense lset) ({
     fullName = "CeCILL Free Software License Agreement v2.0";
   };
 
+  cecill21 = {
+    spdxId = "CECILL-2.1";
+    fullName = "CeCILL Free Software License Agreement v2.1";
+  };
+
   cecill-b = {
     spdxId = "CECILL-B";
     fullName  = "CeCILL-B Free Software License Agreement";
diff --git a/maintainers/maintainer-list.nix b/maintainers/maintainer-list.nix
index 13c23576dae6..0326ca7a9824 100644
--- a/maintainers/maintainer-list.nix
+++ b/maintainers/maintainer-list.nix
@@ -2599,6 +2599,10 @@
     githubId = 202798;
     name = "Pierre Bourdon";
   };
+  delta = {
+    email = "d4delta@outlook.fr";
+    name = "Delta";
+  };
   deltaevo = {
     email = "deltaduartedavid@gmail.com";
     github = "DeltaEvo";
diff --git a/pkgs/development/ocaml-modules/lustre-v6/default.nix b/pkgs/development/ocaml-modules/lustre-v6/default.nix
new file mode 100644
index 000000000000..34feaf85c3f3
--- /dev/null
+++ b/pkgs/development/ocaml-modules/lustre-v6/default.nix
@@ -0,0 +1,28 @@
+{ lib, buildDunePackage, fetchurl, ocaml_extlib, lutils, rdbg }:
+
+buildDunePackage rec {
+  pname = "lustre-v6";
+  version = "6.103.3";
+
+  useDune2 = true;
+
+  minimalOCamlVersion = "4.05";
+
+  src = fetchurl {
+    url = "http://www-verimag.imag.fr/DIST-TOOLS/SYNCHRONE/pool/lustre-v6.6.103.3.tgz";
+    sha512 = "8d452184ee68edda1b5a50717e6a5b13fb21f9204634fc5898280e27a1d79c97a6e7cc04424fc22f34cdd02ed3cc8774dca4f982faf342980b5f9fe0dc1a017d";
+  };
+
+  propagatedBuildInputs = [
+    ocaml_extlib
+    lutils
+    rdbg
+  ];
+
+  meta = with lib; {
+    homepage = "http://www-verimag.imag.fr/lustre-v6.html";
+    description = "Lustre V6 compiler";
+    license = lib.licenses.cecill21;
+    maintainers = [ lib.maintainers.delta ];
+  };
+}
diff --git a/pkgs/development/ocaml-modules/lutils/default.nix b/pkgs/development/ocaml-modules/lutils/default.nix
new file mode 100644
index 000000000000..492a987dc9cc
--- /dev/null
+++ b/pkgs/development/ocaml-modules/lutils/default.nix
@@ -0,0 +1,25 @@
+{ lib, buildDunePackage, fetchurl, num }:
+
+buildDunePackage rec {
+  pname = "lutils";
+  version = "1.51.2";
+
+  useDune2 = true;
+
+  minimalOCamlVersion = "4.02";
+
+  src = fetchurl {
+    url = "http://www-verimag.imag.fr/DIST-TOOLS/SYNCHRONE/pool/lutils.1.51.2.tgz";
+    sha512 = "f94696be379c62e888410ec3d940c888ca4b607cf59c2e364e93a2a694da65ebe6d531107198b795e80eecc3c6865eedb02659c7e7c4e15c9b28d74aa35d09f8";
+  };
+
+  propagatedBuildInputs = [
+    num
+  ];
+
+  meta = with lib; {
+    homepage = "https://gricad-gitlab.univ-grenoble-alpes.fr/verimag/synchrone/lutils/";
+    description = "Tools and libs shared by Verimag/synchronous tools (lustre, lutin, rdbg)";
+    license = lib.licenses.cecill21;
+  };
+}
diff --git a/pkgs/development/ocaml-modules/rdbg/default.nix b/pkgs/development/ocaml-modules/rdbg/default.nix
new file mode 100644
index 000000000000..9b33678590d5
--- /dev/null
+++ b/pkgs/development/ocaml-modules/rdbg/default.nix
@@ -0,0 +1,31 @@
+{ lib, buildDunePackage, fetchurl, num, lutils, ounit}:
+
+buildDunePackage rec {
+  pname = "rdbg";
+  version = "1.196.12";
+
+  useDune2 = true;
+
+  minimalOCamlVersion = "4.07";
+
+  src = fetchurl {
+    url = "http://www-verimag.imag.fr/DIST-TOOLS/SYNCHRONE/pool/rdbg.1.196.12.tgz";
+    sha512 = "8e88034b1eda8f1233b4990adc9746782148254c93d8d0c99c246c0d50f306eeb6aa4afcfca8834acb3e268860647f47a24cc6a2d29fb45cac11f098e2ede275";
+  };
+
+  buildInputs = [
+    num
+    ounit
+  ];
+
+  propagatedBuildInputs = [
+    lutils
+  ];
+
+  meta = with lib; {
+    homepage = "https://gricad-gitlab.univ-grenoble-alpes.fr/verimag/synchrone/rdbg";
+    description = "A programmable debugger that targets reactive programs for which a rdbg-plugin exists. Currently two plugins exist : one for Lustre, and one for Lutin (nb: both are synchronous programming languages)";
+    license = lib.licenses.cecill21;
+    maintainers = [ lib.maintainers.delta ];
+  };
+}
diff --git a/pkgs/tools/misc/ledit/default.nix b/pkgs/tools/misc/ledit/default.nix
new file mode 100644
index 000000000000..18efb8c95285
--- /dev/null
+++ b/pkgs/tools/misc/ledit/default.nix
@@ -0,0 +1,29 @@
+{ lib, stdenv, fetchzip, ocaml, camlp5}:
+
+stdenv.mkDerivation {
+  pname = "ledit";
+  version = "2.04";
+
+  src = fetchzip {
+    url = "http://pauillac.inria.fr/~ddr/ledit/distrib/src/ledit-2.04.tgz";
+    sha512 = "16vlv6rcsddwrvsqqiwxdfv5rxvblhrx0k84g7pjibi0an241yx8aqf8cj4f4sgl5xfs3frqrdf12zqwjf2h4jvk8jyhyar8n0nj3g0";
+  };
+
+  preBuild = ''
+    mkdir -p $out/bin
+    substituteInPlace Makefile --replace /bin/rm rm --replace BINDIR=/usr/local/bin BINDIR=$out/bin
+  '';
+
+  buildInputs = [
+    ocaml
+    camlp5
+  ];
+
+  meta = with lib; {
+    homepage = "http://pauillac.inria.fr/~ddr/ledit/";
+    description = "A line editor, allowing to use shell commands with control characters like in emacs";
+    license = licenses.bsd3;
+    maintainers = [ maintainers.delta ];
+    broken = lib.versionOlder ocaml.version "4.03";
+  };
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 819108f9efc8..7fbbf150eee8 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -6919,6 +6919,10 @@ with pkgs;
 
   leatherman = callPackage ../development/libraries/leatherman { };
 
+  ledit = callPackage ../tools/misc/ledit {
+    inherit (ocamlPackages) camlp5;
+  };
+
   ledmon = callPackage ../tools/system/ledmon { };
 
   leela = callPackage ../tools/graphics/leela { };
diff --git a/pkgs/top-level/ocaml-packages.nix b/pkgs/top-level/ocaml-packages.nix
index 3d67ef92f5a2..c9ab3fc2ab85 100644
--- a/pkgs/top-level/ocaml-packages.nix
+++ b/pkgs/top-level/ocaml-packages.nix
@@ -627,6 +627,10 @@ let
 
     lua-ml = callPackage ../development/ocaml-modules/lua-ml { };
 
+    lustre-v6 = callPackage ../development/ocaml-modules/lustre-v6 { };
+
+    lutils = callPackage ../development/ocaml-modules/lutils { };
+
     luv = callPackage ../development/ocaml-modules/luv {
       inherit (pkgs) file;
     };
@@ -1182,6 +1186,8 @@ let
 
     randomconv = callPackage ../development/ocaml-modules/randomconv { };
 
+    rdbg = callPackage ../development/ocaml-modules/rdbg { };
+
     re = callPackage ../development/ocaml-modules/re { };
 
     react = callPackage ../development/ocaml-modules/react { };