uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/development/tools/ocaml/camlidl/default.nix

@@ -0,0 +1,54 @@
+{ lib, stdenv, fetchurl, ocaml, writeText }:
+
+let
+  pname = "camlidl";
+  webpage = "https://caml.inria.fr/pub/old_caml_site/camlidl/";
+in
+stdenv.mkDerivation rec {
+  name = "${pname}-${version}";
+  version = "1.05";
+
+  src = fetchurl {
+    url = "http://caml.inria.fr/pub/old_caml_site/distrib/bazar-ocaml/${pname}-${version}.tar.gz";
+    sha256 = "0483cs66zsxsavcllpw1qqvyhxb39ddil3h72clcd69g7fyxazl5";
+  };
+
+  nativeBuildInputs = [ ocaml ];
+
+  # build fails otherwise
+  enableParallelBuilding = false;
+
+  preBuild = ''
+    mv config/Makefile.unix config/Makefile
+    substituteInPlace config/Makefile --replace BINDIR=/usr/local/bin BINDIR=$out
+    substituteInPlace config/Makefile --replace OCAMLLIB=/usr/local/lib/ocaml OCAMLLIB=$out/lib/ocaml/${ocaml.version}/site-lib/camlidl
+    substituteInPlace config/Makefile --replace CPP=/lib/cpp CPP=${stdenv.cc}/bin/cpp
+    substituteInPlace config/Makefile --replace "OCAMLC=ocamlc -g" "OCAMLC=ocamlc -g -warn-error -31"
+    mkdir -p $out/lib/ocaml/${ocaml.version}/site-lib/camlidl/caml
+  '';
+
+  postInstall = ''
+    cat >$out/lib/ocaml/${ocaml.version}/site-lib/camlidl/META <<EOF
+    # Courtesy of GODI
+    description = "Stub generator"
+    version = "${version}"
+    archive(byte) = "com.cma"
+    archive(native) = "com.cmxa"
+    EOF
+    mkdir -p $out/bin
+    ln -s $out/camlidl $out/bin
+  '';
+
+  setupHook = writeText "setupHook.sh" ''
+    export CAML_LD_LIBRARY_PATH="''${CAML_LD_LIBRARY_PATH-}''${CAML_LD_LIBRARY_PATH:+:}''$1/lib/ocaml/${ocaml.version}/site-lib/${name}/"
+    export NIX_CFLAGS_COMPILE+=" -isystem $1/lib/ocaml/${ocaml.version}/site-lib/camlidl"
+    export NIX_LDFLAGS+=" -L $1/lib/ocaml/${ocaml.version}/site-lib/camlidl"
+  '';
+
+  meta = {
+    description = "A stub code generator and COM binding for Objective Caml";
+    homepage = webpage;
+    license = "LGPL";
+    maintainers = [ lib.maintainers.roconnor ];
+  };
+}

pkgs/development/tools/ocaml/camlp4/default.nix

@@ -0,0 +1,92 @@
+{ lib, stdenv, fetchzip, which, ocaml, ocamlbuild }:
+
+if lib.versionAtLeast ocaml.version "4.14"
+then throw "camlp4 is not available for OCaml ${ocaml.version}"
+else
+
+let param = {
+  "4.02" = {
+     version = "4.02+6";
+     sha256 = "06yl4q0qazl7g25b0axd1gdkfd4qpqzs1gr5fkvmkrcbz113h1hj"; };
+  "4.03" = {
+     version = "4.03+1";
+     sha256 = "1f2ndch6f1m4fgnxsjb94qbpwjnjgdlya6pard44y6n0dqxi1wsq"; };
+  "4.04" = {
+     version = "4.04+1";
+     sha256 = "1ad7rygqjxrc1im95gw9lp8q83nhdaf383f2808f1p63yl42xm7k"; };
+  "4.05" = {
+     version = "4.05+1";
+     sha256 = "0wm795hpwvwpib9c9z6p8kw2fh7p7b2hml6g15z8zry3y7w738sv"; };
+  "4.06" = {
+     version = "4.06+1";
+     sha256 = "0fazfw2l7wdmbwnqc22xby5n4ri1wz27lw9pfzhsbcdrighykysf"; };
+  "4.07" = {
+     version = "4.07+1";
+     sha256 = "0cxl4hkqcvspvkx4f2k83217rh6051fll9i2yz7cw6m3bq57mdvl"; };
+  "4.08" = {
+     version = "4.08+1";
+     sha256 = "0qplawvxwai25bi27niw2cgz2al01kcnkj8wxwhxslpi21z6pyx1"; };
+  "4.09" = {
+     version = "4.09+1";
+     sha256 = "1gr33x6xs1rs0bpyq4vzyfxd6vn47jfkg8imi81db2r0cbs0kxx1"; };
+  "4.10" = {
+     version = "4.10+1";
+     sha256 = "093bc1c28wid5li0jwglnd4p3csxw09fmbs9ffybq2z41a5mgay6"; };
+  "4.11" = {
+     version = "4.11+1";
+     sha256 = "0sn7f6im940qh0ixmx1k738xrwwdvy9g7r19bv5218jb6mh0g068"; };
+  "4.12" = {
+     version = "4.12+1";
+     sha256 = "1cfk5ppnd511vzsr9gc0grxbafmh0m3m897aij198rppzxps5kyz"; };
+  "4.13" = {
+     version = "4.13+1";
+     sha256 = "0fzxa1zdhk74mlxpin7p90flks6sp4gkc0mfclmj9zak15rii55n"; };
+  }.${ocaml.meta.branch};
+in
+
+stdenv.mkDerivation rec {
+  pname = "camlp4";
+  inherit (param) version;
+
+  src = fetchzip {
+    url = "https://github.com/ocaml/camlp4/archive/${version}.tar.gz";
+    inherit (param) sha256;
+  };
+
+  buildInputs = [ which ocaml ocamlbuild ];
+
+  # build fails otherwise
+  enableParallelBuilding = false;
+
+  dontAddPrefix = true;
+
+  preConfigure = ''
+    # increase stack space for spacetime variant of the compiler
+    # https://github.com/ocaml/ocaml/issues/7435
+    # but disallowed by darwin sandbox
+    ulimit -s unlimited || true
+
+    configureFlagsArray=(
+      --bindir=$out/bin
+      --libdir=$out/lib/ocaml/${ocaml.version}/site-lib
+      --pkgdir=$out/lib/ocaml/${ocaml.version}/site-lib
+    )
+  '';
+
+  postConfigure = ''
+    substituteInPlace camlp4/META.in \
+    --replace +camlp4 $out/lib/ocaml/${ocaml.version}/site-lib/camlp4
+  '';
+
+  makeFlags = [ "all" ];
+
+  installTargets = [ "install" "install-META" ];
+
+  dontStrip = true;
+
+  meta = with lib; {
+    description = "A software system for writing extensible parsers for programming languages";
+    homepage = "https://github.com/ocaml/camlp4";
+    platforms = ocaml.meta.platforms or [];
+  };
+}

pkgs/development/tools/ocaml/camlp5/default.nix

@@ -0,0 +1,46 @@
+{ lib, stdenv, fetchFromGitHub, ocaml, perl }:
+
+if lib.versionOlder ocaml.version "4.02"
+|| lib.versionOlder "4.13" ocaml.version
+then throw "camlp5 is not available for OCaml ${ocaml.version}"
+else
+
+stdenv.mkDerivation rec {
+
+  pname = "camlp5";
+  version = "7.14";
+
+  src = fetchFromGitHub {
+    owner = "camlp5";
+    repo = "camlp5";
+    rev = "rel${builtins.replaceStrings [ "." ] [ "" ] version}";
+    sha256 = "1dd68bisbpqn5lq2pslm582hxglcxnbkgfkwhdz67z4w9d5nvr7w";
+  };
+
+  buildInputs = [ ocaml perl ];
+
+  prefixKey = "-prefix ";
+
+  preConfigure = ''
+    configureFlagsArray=(--strict --libdir $out/lib/ocaml/${ocaml.version}/site-lib)
+    patchShebangs ./config/find_stuffversion.pl
+  '';
+
+  buildFlags = [ "world.opt" ];
+
+  dontStrip = true;
+
+  meta = with lib; {
+    description = "Preprocessor-pretty-printer for OCaml";
+    longDescription = ''
+      Camlp5 is a preprocessor and pretty-printer for OCaml programs.
+      It also provides parsing and printing tools.
+    '';
+    homepage = "https://camlp5.github.io/";
+    license = licenses.bsd3;
+    platforms = ocaml.meta.platforms or [];
+    maintainers = with maintainers; [
+      maggesi vbgl
+    ];
+  };
+}

pkgs/development/tools/ocaml/cppo/default.nix

@@ -0,0 +1,67 @@
+{ lib, stdenv, fetchFromGitHub, ocaml, findlib, ocamlbuild
+, buildDunePackage
+}:
+
+let
+  pname = "cppo";
+
+  meta = with lib; {
+    description = "The C preprocessor for OCaml";
+    longDescription = ''
+      Cppo is an equivalent of the C preprocessor targeted at the OCaml language and its variants.
+    '';
+    homepage = "https://github.com/ocaml-community/${pname}";
+    maintainers = [ maintainers.vbgl ];
+    license = licenses.bsd3;
+  };
+
+in
+
+if lib.versionAtLeast ocaml.version "4.02" then
+
+buildDunePackage rec {
+  inherit pname;
+  version = "1.6.9";
+
+  useDune2 = true;
+
+  src = fetchFromGitHub {
+    owner = "ocaml-community";
+    repo = pname;
+    rev = "v${version}";
+    sha256 = "sha256-NdN2QnVRfRq9hEcSAnO2Wha7icDlf2Zg4JQqoEWmErE=";
+  };
+
+  doCheck = true;
+
+  inherit meta;
+}
+
+else
+
+let version = "1.5.0"; in
+
+stdenv.mkDerivation {
+
+  name = "${pname}-${version}";
+
+  src = fetchFromGitHub {
+    owner = "mjambon";
+    repo = pname;
+    rev = "v${version}";
+    sha256 = "1xqldjz9risndnabvadw41fdbi5sa2hl4fnqls7j9xfbby1izbg8";
+  };
+
+  buildInputs = [ ocaml findlib ocamlbuild ];
+
+  inherit meta;
+
+  createFindlibDestdir = true;
+
+  makeFlags = [ "PREFIX=$(out)" ];
+
+  preBuild = ''
+    mkdir -p $out/bin
+  '';
+
+}

pkgs/development/tools/ocaml/cppo/ocamlbuild.nix

@@ -0,0 +1,17 @@
+{ lib, buildDunePackage, cppo, ocamlbuild }:
+
+if lib.versionOlder (lib.getVersion cppo) "1.6"
+then cppo
+else
+
+buildDunePackage rec {
+  pname = "cppo_ocamlbuild";
+
+  inherit (cppo) version useDune2 src;
+
+  propagatedBuildInputs = [ ocamlbuild ];
+
+  meta = cppo.meta // {
+    description = "Plugin to use cppo with ocamlbuild";
+  };
+}

pkgs/development/tools/ocaml/crunch/default.nix

@@ -0,0 +1,30 @@
+{ lib, buildDunePackage, fetchurl, ocaml, cmdliner, ptime }:
+
+buildDunePackage rec {
+
+  pname = "crunch";
+  version = "3.1.0";
+
+  useDune2 = true;
+
+  src = fetchurl {
+    url = "https://github.com/mirage/ocaml-crunch/releases/download/v${version}/crunch-v${version}.tbz";
+    sha256 = "0d26715a4h9r1wibnc12xy690m1kan7hrcgbb5qk8x78zsr67lnf";
+  };
+
+  propagatedBuildInputs = [ cmdliner ptime ];
+
+  outputs = [ "lib" "bin" "out" ];
+
+  installPhase = ''
+    dune install --prefix=$bin --libdir=$lib/lib/ocaml/${ocaml.version}/site-lib/
+  '';
+
+  meta = {
+    homepage = "https://github.com/mirage/ocaml-crunch";
+    description = "Convert a filesystem into a static OCaml module";
+    license = lib.licenses.isc;
+    maintainers = [ lib.maintainers.vbgl ];
+  };
+
+}

pkgs/development/tools/ocaml/dune-release/default.nix

@@ -0,0 +1,62 @@
+{ lib, buildDunePackage, fetchurl, makeWrapper, fetchpatch
+, curly, fmt, bos, cmdliner, re, rresult, logs, fpath
+, odoc, opam-format, opam-core, opam-state, yojson, astring
+, opam, git, findlib, mercurial, bzip2, gnutar, coreutils
+, alcotest
+}:
+
+# don't include dune as runtime dep, so user can
+# choose between dune and dune_2
+let runtimeInputs = [ opam findlib git mercurial bzip2 gnutar coreutils ];
+in buildDunePackage rec {
+  pname = "dune-release";
+  version = "1.5.2";
+
+  minimumOCamlVersion = "4.06";
+
+  src = fetchurl {
+    url = "https://github.com/ocamllabs/${pname}/releases/download/${version}/${pname}-${version}.tbz";
+    sha256 = "1r6bz1zz1al5y762ws3w98d8bnyi5ipffajgczixacmbrxvp3zgx";
+  };
+
+  nativeBuildInputs = [ makeWrapper ];
+  buildInputs = [ curly fmt cmdliner re opam-format opam-state opam-core
+                  rresult logs odoc bos yojson astring fpath ];
+  checkInputs = [ alcotest ] ++ runtimeInputs;
+  doCheck = true;
+
+  useDune2 = true;
+
+  patches = [
+    # add missing git config calls to avoid failing due to the lack of a global git config
+    (fetchpatch {
+      name = "tests-missing-git-config.patch";
+      url = "https://github.com/ocamllabs/dune-release/commit/87e7ffe2a9c574620d4e2fc0d79eed8772eab973.patch";
+      sha256 = "0wrzcpzr54dwrdjdc75mijh78xk4bmsmqs1pci06fb2nf03vbd2k";
+    })
+  ];
+
+  postPatch = ''
+    # remove check for curl in PATH, since curly is patched
+    # to have a fixed path to the binary in nix store
+    sed -i '/must_exist (Cmd\.v "curl"/d' lib/github.ml
+  '';
+
+  preCheck = ''
+    # it fails when it tries to reference "./make_check_deterministic.exe"
+    rm -r tests/bin/check
+  '';
+
+  # tool specific env vars have been deprecated, use PATH
+  preFixup = ''
+    wrapProgram $out/bin/dune-release \
+      --prefix PATH : "${lib.makeBinPath runtimeInputs}"
+  '';
+
+  meta = with lib; {
+    description = "Release dune packages in opam";
+    homepage = "https://github.com/ocamllabs/dune-release";
+    license = licenses.isc;
+    maintainers = with maintainers; [ sternenseemann ];
+  };
+}

pkgs/development/tools/ocaml/dune/1.nix

@@ -0,0 +1,37 @@
+{ stdenv, lib, fetchurl, ocaml, findlib, ncurses }:
+
+if lib.versionOlder ocaml.version "4.02"
+|| lib.versionAtLeast ocaml.version "4.12"
+then throw "dune 1 is not available for OCaml ${ocaml.version}"
+else
+
+stdenv.mkDerivation rec {
+  pname = "dune";
+  version = "1.11.4";
+  src = fetchurl {
+    url = "https://github.com/ocaml/dune/releases/download/${version}/dune-build-info-${version}.tbz";
+    sha256 = "1rkc8lqw30ifjaz8d81la6i8j05ffd0whpxqsbg6dci16945zjvp";
+  };
+
+  nativeBuildInputs = [ ocaml findlib ];
+  buildInputs = [ ncurses ];
+  strictDeps = true;
+
+  buildFlags = [ "release" ];
+  makeFlags = [
+    "PREFIX=${placeholder "out"}"
+    "LIBDIR=$(OCAMLFIND_DESTDIR)"
+  ];
+
+  dontAddPrefix = true;
+  dontAddStaticConfigureFlags = true;
+  configurePlatforms = [];
+
+  meta = with lib; {
+    homepage = "https://dune.build/";
+    description = "A composable build system";
+    maintainers = [ maintainers.vbgl maintainers.marsam ];
+    license = licenses.mit;
+    inherit (ocaml.meta) platforms;
+  };
+}

pkgs/development/tools/ocaml/dune/2.nix

@@ -0,0 +1,35 @@
+{ lib, stdenv, fetchurl, ocaml, findlib }:
+
+if lib.versionOlder ocaml.version "4.08"
+then throw "dune 2 is not available for OCaml ${ocaml.version}"
+else
+
+stdenv.mkDerivation rec {
+  pname = "dune";
+  version = "2.9.3";
+
+  src = fetchurl {
+    url = "https://github.com/ocaml/dune/releases/download/${version}/dune-site-${version}.tbz";
+    sha256 = "sha256:1ml8bxym8sdfz25bx947al7cvsi2zg5lcv7x9w6xb01cmdryqr9y";
+  };
+
+  nativeBuildInputs = [ ocaml findlib ];
+  strictDeps = true;
+
+  buildFlags = "release";
+
+  dontAddPrefix = true;
+  dontAddStaticConfigureFlags = true;
+  configurePlatforms = [];
+
+  installFlags = [ "PREFIX=${placeholder "out"}" "LIBDIR=$(OCAMLFIND_DESTDIR)" ];
+
+  meta = {
+    homepage = "https://dune.build/";
+    description = "A composable build system";
+    changelog = "https://github.com/ocaml/dune/raw/${version}/CHANGES.md";
+    maintainers = [ lib.maintainers.vbgl lib.maintainers.marsam ];
+    license = lib.licenses.mit;
+    inherit (ocaml.meta) platforms;
+  };
+}

pkgs/development/tools/ocaml/dune/3.nix

@@ -0,0 +1,40 @@
+{ lib, stdenv, fetchurl, ocaml, findlib, darwin }:
+
+if lib.versionOlder ocaml.version "4.08"
+then throw "dune 3 is not available for OCaml ${ocaml.version}"
+else
+
+stdenv.mkDerivation rec {
+  pname = "dune";
+  version = "3.2.0";
+
+  src = fetchurl {
+    url = "https://github.com/ocaml/dune/releases/download/${version}/chrome-trace-${version}.tbz";
+    sha256 = "sha256-vR+85q557R6yb6ibsuLiOXivzrP1P1V4zxvasIoa1bw=";
+  };
+
+  nativeBuildInputs = [ ocaml findlib ];
+
+  buildInputs = lib.optionals stdenv.isDarwin [
+    darwin.apple_sdk.frameworks.Foundation
+  ];
+
+  strictDeps = true;
+
+  buildFlags = "release";
+
+  dontAddPrefix = true;
+  dontAddStaticConfigureFlags = true;
+  configurePlatforms = [];
+
+  installFlags = [ "PREFIX=${placeholder "out"}" "LIBDIR=$(OCAMLFIND_DESTDIR)" ];
+
+  meta = {
+    homepage = "https://dune.build/";
+    description = "A composable build system";
+    changelog = "https://github.com/ocaml/dune/raw/${version}/CHANGES.md";
+    maintainers = [ lib.maintainers.vbgl lib.maintainers.marsam ];
+    license = lib.licenses.mit;
+    inherit (ocaml.meta) platforms;
+  };
+}

pkgs/development/tools/ocaml/findlib/default.nix

@@ -0,0 +1,66 @@
+{ lib, stdenv, fetchurl, fetchpatch, m4, ncurses, ocaml, writeText }:
+
+stdenv.mkDerivation rec {
+  pname = "ocaml-findlib";
+  version = "1.9.3";
+
+  src = fetchurl {
+    url = "http://download.camlcity.org/download/findlib-${version}.tar.gz";
+    sha256 = "sha256:0hfcwamcvinmww59b5i4yxbf0kxyzkp5qv3d1c7ybn9q52vgq463";
+  };
+
+  nativeBuildInputs = [m4 ocaml];
+  buildInputs = [ ncurses ];
+
+  patches = [ ./ldconf.patch ./install_topfind.patch ];
+
+  dontAddPrefix=true;
+  dontAddStaticConfigureFlags = true;
+  configurePlatforms = [];
+
+  configureFlags = [
+      "-bindir" "${placeholder "out"}/bin"
+      "-mandir" "${placeholder "out"}/share/man"
+      "-sitelib" "${placeholder "out"}/lib/ocaml/${ocaml.version}/site-lib"
+      "-config" "${placeholder "out"}/etc/findlib.conf"
+  ];
+
+  buildFlags = [ "all" "opt" ];
+
+  setupHook = writeText "setupHook.sh" ''
+    addOCamlPath () {
+        if test -d "''$1/lib/ocaml/${ocaml.version}/site-lib"; then
+            export OCAMLPATH="''${OCAMLPATH-}''${OCAMLPATH:+:}''$1/lib/ocaml/${ocaml.version}/site-lib/"
+        fi
+        if test -d "''$1/lib/ocaml/${ocaml.version}/site-lib/stublibs"; then
+            export CAML_LD_LIBRARY_PATH="''${CAML_LD_LIBRARY_PATH-}''${CAML_LD_LIBRARY_PATH:+:}''$1/lib/ocaml/${ocaml.version}/site-lib/stublibs"
+        fi
+    }
+    exportOcamlDestDir () {
+        export OCAMLFIND_DESTDIR="''$out/lib/ocaml/${ocaml.version}/site-lib/"
+    }
+    createOcamlDestDir () {
+        if test -n "''${createFindlibDestdir-}"; then
+          mkdir -p $OCAMLFIND_DESTDIR
+        fi
+    }
+
+    # run for every buildInput
+    addEnvHooks "$targetOffset" addOCamlPath
+    # run before installPhase, even without buildInputs, and not in nix-shell
+    preInstallHooks+=(createOcamlDestDir)
+    # run even in nix-shell, and even without buildInputs
+    addEnvHooks "$hostOffset" exportOcamlDestDir
+  '';
+
+  meta = {
+    description = "O'Caml library manager";
+    homepage = "http://projects.camlcity.org/projects/findlib.html";
+    license = lib.licenses.mit;
+    maintainers = with lib.maintainers; [ maggesi vbmithr ];
+    mainProgram = "ocamlfind";
+    platforms = ocaml.meta.platforms or [];
+  };
+}
+
+

pkgs/development/tools/ocaml/findlib/install_topfind.patch

@@ -0,0 +1,12 @@
+--- a/src/findlib/Makefile
++++ b/src/findlib/Makefile
+@@ -123,7 +123,7 @@ clean:
+ install: all
+ 	mkdir -p "$(prefix)$(OCAML_SITELIB)/$(NAME)"
+ 	mkdir -p "$(prefix)$(OCAMLFIND_BIN)"
+-	test $(INSTALL_TOPFIND) -eq 0 || cp topfind "$(prefix)$(OCAML_CORE_STDLIB)"
++	test $(INSTALL_TOPFIND) -eq 0 || cp topfind "$(prefix)$(OCAML_SITELIB)"
+ 	files=`$(SH) $(TOP)/tools/collect_files $(TOP)/Makefile.config \
+ 	findlib.cmi findlib.mli findlib.cma findlib.cmxa findlib$(LIB_SUFFIX) findlib.cmxs \
+ 	findlib_config.cmi findlib_config.ml topfind.cmi topfind.mli \
+

pkgs/development/tools/ocaml/findlib/ldconf.patch

@@ -0,0 +1,8 @@
+Setting paths to search for dnynmic libraries isn't very useful in Nix.
+
+--- findlib-1.2.6/findlib.conf.in	2010-08-17 14:50:28.000000000 -0400
++++ findlib-1.2.6/findlib.conf.in	2010-11-24 09:46:55.179648354 -0500
+@@ -1,2 +1,3 @@
+ destdir="@SITELIB@"
+ path="@SITELIB@"
++ldconf="ignore"

pkgs/development/tools/ocaml/js_of_ocaml/Makefile.conf.diff

@@ -0,0 +1,10 @@
+--- old/Makefile.conf	2014-05-19 16:53:09.263564921 +0200
++++ new/Makefile.conf	2014-05-19 16:53:42.213152994 +0200
+@@ -1,6 +1,6 @@
+ 
+ # Where binaries are installed:
+-BINDIR := `dirname  \`which ocamlc\``
++BINDIR := $(out)/bin
+ 
+ ####
+ 

pkgs/development/tools/ocaml/js_of_ocaml/camlp4.nix

@@ -0,0 +1,21 @@
+{ buildDunePackage, fetchFromGitHub, js_of_ocaml-compiler
+, camlp4, ocsigen_deriving
+}:
+
+buildDunePackage rec {
+  version = "3.2.1";
+  pname = "js_of_ocaml-camlp4";
+
+  useDune2 = false;
+
+  src = fetchFromGitHub {
+    owner = "ocsigen";
+    repo = "js_of_ocaml";
+    rev = version;
+    sha256 = "1v2hfq0ra9j07yz6pj6m03hrvgys4vmx0gclchv94yywpb2wc7ik";
+  };
+
+  buildInputs = [ camlp4 ocsigen_deriving ];
+
+  meta = builtins.removeAttrs js_of_ocaml-compiler.meta [ "mainProgram" ];
+}

pkgs/development/tools/ocaml/js_of_ocaml/compiler.nix

@@ -0,0 +1,29 @@
+{ lib, fetchurl, buildDunePackage
+, cmdliner, yojson, ppxlib
+, menhir, menhirLib
+}:
+
+buildDunePackage rec {
+  pname = "js_of_ocaml-compiler";
+  version = "4.0.0";
+  useDune2 = true;
+
+  src = fetchurl {
+    url = "https://github.com/ocsigen/js_of_ocaml/releases/download/${version}/js_of_ocaml-${version}.tbz";
+    sha256 = "sha256:0pj9jjrmi0xxrzmygv4b5whsibw1jxy3wgibmws85x5jwlczh0nz";
+  };
+
+  nativeBuildInputs = [ menhir ];
+  buildInputs = [ cmdliner ppxlib ];
+
+  configurePlatforms = [];
+  propagatedBuildInputs = [ menhirLib yojson ];
+
+  meta = {
+    description = "Compiler from OCaml bytecode to Javascript";
+    homepage = "https://ocsigen.org/js_of_ocaml/";
+    license = lib.licenses.gpl2;
+    maintainers = [ lib.maintainers.vbgl ];
+    mainProgram = "js_of_ocaml";
+  };
+}

pkgs/development/tools/ocaml/js_of_ocaml/default.nix

@@ -0,0 +1,15 @@
+{ buildDunePackage, js_of_ocaml-compiler
+, ppxlib, uchar
+}:
+
+buildDunePackage {
+  pname = "js_of_ocaml";
+
+  inherit (js_of_ocaml-compiler) version src useDune2;
+
+  buildInputs = [ ppxlib ];
+
+  propagatedBuildInputs = [ js_of_ocaml-compiler uchar ];
+
+  meta = builtins.removeAttrs js_of_ocaml-compiler.meta [ "mainProgram" ];
+}

pkgs/development/tools/ocaml/js_of_ocaml/lwt.nix

@@ -0,0 +1,15 @@
+{ buildDunePackage, js_of_ocaml-compiler, js_of_ocaml-ppx
+, js_of_ocaml, ocaml_lwt, lwt_log
+}:
+
+buildDunePackage {
+  pname = "js_of_ocaml-lwt";
+
+  inherit (js_of_ocaml-compiler) version src useDune2;
+
+  buildInputs = [ js_of_ocaml-ppx ];
+
+  propagatedBuildInputs = [ js_of_ocaml ocaml_lwt lwt_log ];
+
+  meta = builtins.removeAttrs js_of_ocaml-compiler.meta [ "mainProgram" ];
+}

pkgs/development/tools/ocaml/js_of_ocaml/ocamlbuild.nix

@@ -0,0 +1,26 @@
+{ lib, buildDunePackage, fetchFromGitHub
+, ocamlbuild
+}:
+
+buildDunePackage rec {
+  pname = "js_of_ocaml-ocamlbuild";
+  version = "4.0.0";
+
+  minimalOCamlVersion = "4.02";
+
+  src = fetchFromGitHub {
+    owner = "ocsigen";
+    repo = pname;
+    rev = "852302c8f35b946e2ec275c529a79e46d8749be6";
+    sha256 = "sha256:03ayvakvbh4wi4dwcgd7r9y8ka8cv3d59hb81yk2dxyd94bln145";
+  };
+
+  propagatedBuildInputs = [ ocamlbuild ];
+
+  meta = {
+    description = "An ocamlbuild plugin to compile to JavaScript";
+    license = lib.licenses.lgpl2Only;
+    maintainers = [ lib.maintainers.vbgl ];
+    inherit (src.meta) homepage;
+  };
+}

pkgs/development/tools/ocaml/js_of_ocaml/ppx.nix

@@ -0,0 +1,15 @@
+{ buildDunePackage, js_of_ocaml-compiler
+, ppxlib
+, js_of_ocaml
+}:
+
+buildDunePackage {
+  pname = "js_of_ocaml-ppx";
+
+  inherit (js_of_ocaml-compiler) version src useDune2;
+
+  buildInputs = [ js_of_ocaml ];
+  propagatedBuildInputs = [ ppxlib ];
+
+  meta = builtins.removeAttrs js_of_ocaml-compiler.meta [ "mainProgram" ];
+}

pkgs/development/tools/ocaml/js_of_ocaml/ppx_deriving_json.nix

@@ -0,0 +1,13 @@
+{ buildDunePackage, js_of_ocaml-compiler
+, js_of_ocaml, ppxlib
+}:
+
+buildDunePackage {
+  pname = "js_of_ocaml-ppx_deriving_json";
+
+  inherit (js_of_ocaml-compiler) version src useDune2;
+
+  propagatedBuildInputs = [ js_of_ocaml ppxlib ];
+
+  meta = builtins.removeAttrs js_of_ocaml-compiler.meta [ "mainProgram" ];
+}

pkgs/development/tools/ocaml/js_of_ocaml/tyxml.nix

@@ -0,0 +1,16 @@
+{ buildDunePackage, js_of_ocaml-compiler
+, js_of_ocaml-ppx
+, js_of_ocaml, reactivedata, tyxml
+}:
+
+buildDunePackage {
+  pname = "js_of_ocaml-tyxml";
+
+  inherit (js_of_ocaml-compiler) version src useDune2;
+
+  buildInputs = [ js_of_ocaml-ppx ];
+
+  propagatedBuildInputs = [ js_of_ocaml reactivedata tyxml ];
+
+  meta = builtins.removeAttrs js_of_ocaml-compiler.meta [ "mainProgram" ];
+}

pkgs/development/tools/ocaml/merlin/4.x.nix

@@ -0,0 +1,88 @@
+{ lib
+, substituteAll
+, fetchurl
+, ocaml
+, dune_2
+, buildDunePackage
+, yojson
+, csexp
+, result
+, dot-merlin-reader
+, jq
+, menhir
+, menhirLib
+, menhirSdk
+}:
+
+let
+  merlinVersion = "4.5";
+
+  hashes = {
+    "4.5-411" = "sha256:05nz6y7r91rh0lj8b6xdv3s3yknmvjc7y60v17kszgqnr887bvpn";
+    "4.5-412" = "sha256:0i5c3rfzinmwdjya7gv94zyknsm32qx9dlg472xpfqivwvnnhf1z";
+    "4.5-413" = "sha256:1sphq9anfg1qzrvj7hdcqflj6cmc1qiyfkljhng9fxnnr0i7550s";
+    "4.5-414" = "sha256:13h588kwih05zd9p3p7q528q4zc0d1l983kkvbmkxgay5d17nn1i";
+  };
+
+  ocamlVersionShorthand = lib.concatStrings
+    (lib.take 2 (lib.splitVersion ocaml.version));
+
+  version = "${merlinVersion}-${ocamlVersionShorthand}";
+in
+
+if !lib.hasAttr version hashes
+then builtins.throw "merlin ${merlinVersion} is not available for OCaml ${ocaml.version}"
+else
+
+buildDunePackage {
+  pname = "merlin";
+  inherit version;
+
+  src = fetchurl {
+    url = "https://github.com/ocaml/merlin/releases/download/v${version}/merlin-${version}.tbz";
+    sha256 = hashes."${version}";
+  };
+
+  patches = [
+    (substituteAll {
+      src = ./fix-paths.patch;
+      dot_merlin_reader = "${dot-merlin-reader}/bin/dot-merlin-reader";
+      dune = "${dune_2}/bin/dune";
+    })
+  ] ++ lib.optional (lib.versionOlder ocaml.version "4.12")
+    # This fixes the test-suite on macOS
+    # See https://github.com/ocaml/merlin/pull/1399
+    # Fixed in 4.4 for OCaml ≥ 4.12
+    ./test.patch
+  ;
+
+  strictDeps = true;
+
+  nativeBuildInputs = [
+    menhir
+    jq
+  ];
+  buildInputs = [
+    dot-merlin-reader
+    yojson
+    csexp
+    result
+    menhirSdk
+    menhirLib
+  ];
+
+  doCheck = true;
+  checkPhase = ''
+    runHook preCheck
+    patchShebangs tests/merlin-wrapper
+    dune runtest # filtering with -p disables tests
+    runHook postCheck
+  '';
+
+  meta = with lib; {
+    description = "An editor-independent tool to ease the development of programs in OCaml";
+    homepage = "https://github.com/ocaml/merlin";
+    license = licenses.mit;
+    maintainers = [ maintainers.vbgl maintainers.sternenseemann ];
+  };
+}

pkgs/development/tools/ocaml/merlin/default.nix

@@ -0,0 +1,35 @@
+{ lib, fetchurl, buildDunePackage, substituteAll
+, dot-merlin-reader, dune_2, yojson, csexp, result, menhirSdk }:
+
+buildDunePackage rec {
+  pname = "merlin";
+  version = "3.4.2";
+
+  src = fetchurl {
+    url = "https://github.com/ocaml/merlin/releases/download/v${version}/merlin-v${version}.tbz";
+    sha256 = "e1b7b897b11119d92995c558530149fd07bd67a4aaf140f55f3c4ffb5e882a81";
+  };
+
+  useDune2 = true;
+
+  minimumOCamlVersion = "4.02.3";
+
+  patches = [
+    (substituteAll {
+      src = ./fix-paths.patch;
+      dot_merlin_reader = "${dot-merlin-reader}/bin/dot-merlin-reader";
+      dune = "${dune_2}/bin/dune";
+    })
+  ];
+
+  strictDeps = true;
+
+  buildInputs = [ dot-merlin-reader yojson csexp result menhirSdk ];
+
+  meta = with lib; {
+    description = "An editor-independent tool to ease the development of programs in OCaml";
+    homepage = "https://github.com/ocaml/merlin";
+    license = licenses.mit;
+    maintainers = [ maintainers.vbgl ];
+  };
+}

pkgs/development/tools/ocaml/merlin/dot-merlin-reader.nix

@@ -0,0 +1,24 @@
+{ lib, fetchurl, yojson, csexp, result, buildDunePackage }:
+
+buildDunePackage rec {
+  pname = "dot-merlin-reader";
+  version = "4.1";
+
+  useDune2 = true;
+
+  minimumOCamlVersion = "4.06";
+
+  src = fetchurl {
+    url = "https://github.com/ocaml/merlin/releases/download/v${version}/dot-merlin-reader-v${version}.tbz";
+    sha256 = "14a36d6fb8646a5df4530420a7861722f1a4ee04753717947305e3676031e7cd";
+  };
+
+  buildInputs = [ yojson csexp result ];
+
+  meta = with lib; {
+    description = "Reads config files for merlin";
+    homepage = "https://github.com/ocaml/merlin";
+    license = licenses.mit;
+    maintainers = [ maintainers.hongchangwu ];
+  };
+}

pkgs/development/tools/ocaml/merlin/fix-paths.patch

@@ -0,0 +1,15 @@
+--- a/src/kernel/mconfig_dot.ml
++++ b/src/kernel/mconfig_dot.ml
+@@ -126,10 +126,10 @@ module Configurator = struct
+       let prog, args =
+         match cfg with
+         | Dot_merlin ->
+-          let prog = "dot-merlin-reader" in
++          let prog = "@dot_merlin_reader@" in
+           prog, [| prog |]
+         | Dune ->
+-          let prog = "dune" in
++          let prog = "@dune@" in
+           prog, [| prog; "ocaml-merlin"; "--no-print-directory" |]
+       in
+       log ~title:"get_config" "Using %s configuration provider." (to_string cfg);

pkgs/development/tools/ocaml/merlin/test.patch

@@ -0,0 +1,19 @@
+commit 282eed37f39ff216add8d53766fd59f3737eb87f
+Author: Vincent Laporte <Vincent.Laporte@gmail.com>
+Date:   Thu Nov 4 06:24:07 2021 +0100
+
+    Ignore dune stderr in tests
+
+diff --git a/tests/test-dirs/document/src-documentation.t/run.t b/tests/test-dirs/document/src-documentation.t/run.t
+index 2c9e1419..4f4c4327 100644
+--- a/tests/test-dirs/document/src-documentation.t/run.t
++++ b/tests/test-dirs/document/src-documentation.t/run.t
+@@ -42,7 +42,7 @@ documentation for the non-last defined value (in the same file) is show
+   > jq '.value'
+   " List reversal. "
+ 
+-  $ dune build --root=. ./doc.exe
++  $ dune build --root=. ./doc.exe 2> /dev/null
+   $ cat >.merlin <<EOF
+   > B _build/default/.doc.eobjs/byte
+   > S .

pkgs/development/tools/ocaml/oasis/default.nix

@@ -0,0 +1,49 @@
+{ lib, stdenv, fetchurl, ocaml, findlib, ocamlbuild, ocamlmod, ocamlify }:
+
+stdenv.mkDerivation {
+  version = "0.4.10";
+  pname = "ocaml-oasis";
+
+  # You must manually update the url, not just the version. OCamlforge keys off
+  # the number after download.php, not the filename.
+  src = fetchurl {
+    url = "https://forge.ocamlcore.org/frs/download.php/1694/oasis-0.4.10.tar.gz";
+    sha256 = "13ah03pbcvrjv5lmx971hvkm9rvbvimska5wmjfvgvd20ca0gn8w";
+  };
+
+  createFindlibDestdir = true;
+
+  strictDeps = true;
+
+  nativeBuildInputs =
+    [
+      ocaml findlib ocamlbuild ocamlmod ocamlify
+    ];
+
+  buildInputs = [ ocamlbuild ];
+
+  configurePhase = ''
+    runHook preConfigure
+    ocaml setup.ml -configure --prefix $out
+    runHook postConfigure
+  '';
+  buildPhase = ''
+    runHook preBuild
+    ocaml setup.ml -build
+    runHook postBuild
+  '';
+  installPhase = ''
+    runHook preInstall
+    ocaml setup.ml -install
+    runHook postInstall
+  '';
+
+  meta = with lib; {
+    description = "Configure, build and install system for OCaml projects";
+    homepage = "http://oasis.forge.ocamlcore.org/";
+    license = licenses.lgpl21;
+    maintainers = with maintainers; [ vbgl maggesi ];
+    mainProgram = "oasis";
+    platforms = ocaml.meta.platforms or [];
+  };
+}

pkgs/development/tools/ocaml/obelisk/default.nix

@@ -0,0 +1,25 @@
+{ lib, fetchFromGitHub, ocamlPackages, menhir }:
+
+ocamlPackages.buildDunePackage rec {
+  pname = "obelisk";
+  version = "0.6.0";
+  useDune2 = true;
+  src = fetchFromGitHub {
+    owner = "Lelio-Brun";
+    repo = pname;
+    rev = "v${version}";
+    sha256 = "1jjaqa2b7msl9qd3x7j34vdh1s9alq8hbvzk8a5srb4yyfyim15b";
+  };
+
+  strictDeps = true;
+
+  nativeBuildInputs = [ menhir ];
+  buildInputs = with ocamlPackages; [ re ];
+
+  meta = {
+    description = "A simple tool which produces pretty-printed output from a Menhir parser file (.mly)";
+    license = lib.licenses.mit;
+    maintainers = [ lib.maintainers.vbgl ];
+    homepage = "https://github.com/Lelio-Brun/Obelisk";
+  };
+}

pkgs/development/tools/ocaml/obuild/default.nix

@@ -0,0 +1,33 @@
+{ lib, stdenv, fetchFromGitHub, ocaml }:
+
+stdenv.mkDerivation rec {
+  pname = "obuild";
+  version = "0.1.10";
+
+  src = fetchFromGitHub {
+    owner = "ocaml-obuild";
+    repo = "obuild";
+    rev = "obuild-v${version}";
+    sha256 = "sha256-dqWP9rwWmr7i3O29v/kipJL01B3qQozaToOFCdfTWZU=";
+  };
+
+  buildInputs = [ ocaml ];
+
+  buildPhase = ''
+    patchShebangs ./bootstrap
+    ./bootstrap
+  '';
+
+  installPhase = ''
+    mkdir -p $out/bin
+    cp dist/build/obuild/obuild dist/build/obuild-from-oasis/obuild-from-oasis dist/build/obuild-simple/obuild-simple $out/bin/
+  '';
+
+  meta = {
+    homepage = "https://github.com/ocaml-obuild/obuild";
+    platforms = ocaml.meta.platforms or [ ];
+    description = "Simple package build system for OCaml";
+    license = lib.licenses.lgpl21;
+    maintainers = with lib.maintainers; [ volth ];
+  };
+}

pkgs/development/tools/ocaml/ocaml-recovery-parser/default.nix

@@ -0,0 +1,36 @@
+{ lib
+, fetchFromGitHub
+, buildDunePackage
+, fix
+, menhirLib
+, menhirSdk
+}:
+
+buildDunePackage rec {
+  pname = "ocaml-recovery-parser";
+  version = "0.2.2";
+
+  minimalOCamlVersion = "4.08";
+  useDune2 = true;
+
+  src = fetchFromGitHub {
+    owner = "serokell";
+    repo = pname;
+    rev = version;
+    sha256 = "qQHvAPNQBbsvlQRh19sz9BtfhhMOp3uPthVozc1fpw8=";
+  };
+
+  propagatedBuildInputs = [
+    fix
+    menhirLib
+    menhirSdk
+  ];
+
+  meta = with lib; {
+    description = "A simple fork of OCaml parser with support for error recovery";
+    homepage = "https://github.com/serokell/ocaml-recovery-parser";
+    license = with licenses; [ lgpl2Only mit mpl20 ];
+    maintainers = with maintainers; [ romildo ];
+    mainProgram = "menhir-recover";
+  };
+}

pkgs/development/tools/ocaml/ocaml-top/default.nix

@@ -0,0 +1,29 @@
+{ lib, fetchFromGitHub, ncurses, ocamlPackages }:
+
+with ocamlPackages; buildDunePackage rec {
+  pname = "ocaml-top";
+  version = "1.2.0-rc";
+
+  useDune2 = true;
+
+  src = fetchFromGitHub {
+    owner = "OCamlPro";
+    repo = "ocaml-top";
+    rev = version;
+    sha256 = "sha256-ZXnPnPvJmHshkTwYWeBojrgJYAF/R6vUo0XkvVMFSeQ=";
+  };
+
+  buildInputs = [ ncurses ocp-build lablgtk3-sourceview3 ocp-index ];
+
+  configurePhase = ''
+    export TERM=xterm
+    ocp-build -init
+  '';
+
+  meta = {
+    homepage = "https://www.typerex.org/ocaml-top.html";
+    license = lib.licenses.gpl3;
+    description = "A simple cross-platform OCaml code editor built for top-level evaluation";
+    maintainers = with lib.maintainers; [ vbgl ];
+  };
+}

pkgs/development/tools/ocaml/ocamlbuild/default.nix

@@ -0,0 +1,41 @@
+{ lib, stdenv, fetchFromGitHub, ocaml, findlib }:
+stdenv.mkDerivation rec {
+  pname = "ocaml${ocaml.version}-ocamlbuild";
+  version = "0.14.1";
+
+  src = fetchFromGitHub {
+    owner = "ocaml";
+    repo = "ocamlbuild";
+    rev = version;
+    sha256 = "sha256-ZL0BwOCWTNDjNkrwNAmzHjHF1Rpg3CUuV4lSqcwDqgI=";
+  };
+
+  createFindlibDestdir = true;
+
+  nativeBuildInputs = [ ocaml findlib ];
+  strictDeps = true;
+
+  # x86_64-unknown-linux-musl-ld: -r and -pie may not be used together
+  hardeningDisable = lib.optional stdenv.hostPlatform.isStatic "pie";
+
+  configurePhase = ''
+  runHook preConfigure
+
+  make -f configure.make Makefile.config \
+    "OCAMLBUILD_PREFIX=$out" \
+    "OCAMLBUILD_BINDIR=$out/bin" \
+    "OCAMLBUILD_MANDIR=$out/share/man" \
+    "OCAMLBUILD_LIBDIR=$OCAMLFIND_DESTDIR"
+
+  runHook postConfigure
+  '';
+
+  meta = with lib; {
+    description = "A build system with builtin rules to easily build most OCaml projects";
+    homepage = "https://github.com/ocaml/ocamlbuild/";
+    license = licenses.lgpl2;
+    maintainers = with maintainers; [ vbgl ];
+    mainProgram = "ocamlbuild";
+    inherit (ocaml.meta) platforms;
+  };
+}

pkgs/development/tools/ocaml/ocamlformat/default.nix

@@ -0,0 +1,31 @@
+{ lib, fetchurl, fetchzip, callPackage }:
+
+let mkOCamlformat = callPackage ./generic.nix; in
+
+# Older versions should be removed when their usage decrease
+# This script scraps Github looking for OCamlformat's options and versions usage:
+#  https://gist.github.com/Julow/110dc94308d6078225e0665e3eccd433
+
+rec {
+  ocamlformat_0_19_0 = mkOCamlformat {
+    version = "0.19.0";
+  };
+
+  ocamlformat_0_20_0 = mkOCamlformat {
+    version = "0.20.0";
+  };
+
+  ocamlformat_0_20_1 = mkOCamlformat {
+    version = "0.20.1";
+  };
+
+  ocamlformat_0_21_0 = mkOCamlformat {
+    version = "0.21.0";
+  };
+
+  ocamlformat_0_22_4 = mkOCamlformat {
+    version = "0.22.4";
+  };
+
+  ocamlformat = ocamlformat_0_22_4;
+}

pkgs/development/tools/ocaml/ocamlformat/generic.nix

@@ -0,0 +1,64 @@
+{ lib, fetchurl, fetchzip, ocaml-ng
+, version
+, tarballName ? "ocamlformat-${version}.tbz",
+}:
+
+let src =
+  fetchurl {
+    url = "https://github.com/ocaml-ppx/ocamlformat/releases/download/${version}/${tarballName}";
+    sha256 = {
+      "0.19.0" = "0ihgwl7d489g938m1jvgx8azdgq9f5np5mzqwwya797hx2m4dz32";
+      "0.20.0" = "sha256-JtmNCgwjbCyUE4bWqdH5Nc2YSit+rekwS43DcviIfgk=";
+      "0.20.1" = "sha256-fTpRZFQW+ngoc0T6A69reEUAZ6GmHkeQvxspd5zRAjU=";
+      "0.21.0" = "sha256-KhgX9rxYH/DM6fCqloe4l7AnJuKrdXSe6Y1XY3BXMy0=";
+      "0.22.4" = "sha256-61TeK4GsfMLmjYGn3ICzkagbc3/Po++Wnqkb2tbJwGA=";
+    }."${version}";
+  };
+  ocamlPackages = ocaml-ng.ocamlPackages;
+in
+
+with ocamlPackages;
+
+buildDunePackage {
+  pname = "ocamlformat";
+  inherit src version;
+
+  minimumOCamlVersion = "4.08";
+
+  useDune2 = true;
+
+  strictDeps = true;
+
+  nativeBuildInputs = [
+    menhir
+  ];
+
+  buildInputs = [
+    base
+    dune-build-info
+    fix
+    fpath
+    menhirLib
+    menhirSdk
+    ocp-indent
+    re
+    stdio
+    uuseg
+    uutf
+  ]
+  ++ lib.optionals (lib.versionAtLeast version "0.20.0") [ ocaml-version either ]
+  ++ (if lib.versionAtLeast version "0.20.1"
+      then [ odoc-parser ]
+      else [ (odoc-parser.override { version = "0.9.0"; }) ])
+  ++ (if lib.versionAtLeast version "0.21.0"
+      then [ cmdliner_1_1 ]
+      else [ cmdliner_1_0 ])
+  ++ lib.optionals (lib.versionAtLeast version "0.22.4") [ csexp ];
+
+  meta = {
+    homepage = "https://github.com/ocaml-ppx/ocamlformat";
+    description = "Auto-formatter for OCaml code";
+    maintainers = [ lib.maintainers.Zimmi48 lib.maintainers.marsam ];
+    license = lib.licenses.mit;
+  };
+}

pkgs/development/tools/ocaml/ocamlify/default.nix

@@ -0,0 +1,36 @@
+{ lib, stdenv, fetchurl, ocaml, findlib, ocamlbuild }:
+
+stdenv.mkDerivation rec {
+  pname = "ocamlify";
+  version = "0.0.2";
+
+  src = fetchurl {
+    url = "https://forge.ocamlcore.org/frs/download.php/1209/${pname}-${version}.tar.gz";
+    sha256 = "1f0fghvlbfryf5h3j4as7vcqrgfjb4c8abl5y0y5h069vs4kp5ii";
+  };
+
+  buildInputs = [ ocaml findlib ocamlbuild ];
+
+  configurePhase = ''
+    substituteInPlace src/ocamlify.ml --replace 'OCamlifyConfig.version' '"0.0.2"'
+  '';
+
+  buildPhase = "ocamlbuild src/ocamlify.native";
+
+  installPhase = ''
+    mkdir -p $out/bin
+    mv _build/src/ocamlify.native $out/bin/ocamlify
+  '';
+
+  dontStrip = true;
+
+  meta = {
+    homepage = "https://forge.ocamlcore.org/projects/ocamlmod/ocamlmod";
+    description = "Generate OCaml modules from source files";
+    platforms = ocaml.meta.platforms or [];
+    license = lib.licenses.lgpl21;
+    maintainers = with lib.maintainers; [
+      maggesi
+    ];
+  };
+}

pkgs/development/tools/ocaml/ocamlmod/default.nix

@@ -0,0 +1,39 @@
+{ lib, stdenv, fetchurl, ocaml, findlib, ocamlbuild, ounit }:
+
+let
+  # ounit is only available for OCaml >= 4.04
+  doCheck = lib.versionAtLeast ocaml.version "4.04";
+in
+
+stdenv.mkDerivation {
+  pname = "ocamlmod";
+  version = "0.0.9";
+
+  src = fetchurl {
+    url = "https://forge.ocamlcore.org/frs/download.php/1702/ocamlmod-0.0.9.tar.gz";
+    sha256 = "0cgp9qqrq7ayyhddrmqmq1affvfqcn722qiakjq4dkywvp67h4aa";
+  };
+
+  buildInputs = [ ocaml findlib ocamlbuild ];
+
+  configurePhase = "ocaml setup.ml -configure --prefix $out"
+    + lib.optionalString doCheck " --enable-tests";
+  buildPhase     = "ocaml setup.ml -build";
+  installPhase   = "ocaml setup.ml -install";
+
+  inherit doCheck;
+  checkInputs = [ ounit ];
+
+  checkPhase = "ocaml setup.ml -test";
+
+  dontStrip = true;
+
+  meta = {
+    homepage = "https://forge.ocamlcore.org/projects/ocamlmod/ocamlmod";
+    description = "Generate OCaml modules from source files";
+    platforms = ocaml.meta.platforms or [];
+    maintainers = with lib.maintainers; [
+      maggesi
+    ];
+  };
+}

pkgs/development/tools/ocaml/ocamlscript/Makefile.patch

@@ -0,0 +1,67 @@
+diff --git a/Makefile b/Makefile
+index 894e94d..9adc44b 100644
+--- a/Makefile
++++ b/Makefile
+@@ -17,7 +17,7 @@ ifndef BINDIR
+ endif
+ export BINDIR
+ 
+-PACKS = unix str
++PACKS = unix str findlib
+ # PP = camlp4o -I . -parser pa_opt.cmo
+ # export PP
+ 
+diff --git a/main.ml b/main.ml
+index 288526a..b67c5e9 100644
+--- a/main.ml
++++ b/main.ml
+@@ -247,6 +247,11 @@ let write_header ~pos ~source ~source_option ~verbose ~prog_file lines =
+ 		    Sys.getcwd ())
+     | `File script_name -> "", get_dir script_name in
+ 
++  let findlibdir =
++    Filename.(
++      concat (Findlib.package_directory "findlib") parent_dir_name
++    ) in
++
+   let file, oc = Filename.open_temp_file "meta" ".ml" in
+   fprintf oc "\
+ #%i %S;;
+@@ -255,6 +260,7 @@ let () =
+   try Topdirs.dir_directory (Sys.getenv \"OCAML_TOPLEVEL_PATH\")
+   with Not_found -> ()
+ ;;
++#directory \"%s\";;
+ #use \"topfind\";;
+ #require \"ocamlscript\";;
+ Ocamlscript.Common.verbose := %s;;
+@@ -263,7 +269,7 @@ Ocamlscript.Common.script_dir := %S;;
+ open Ocamlscript;;
+ open Utils;;
+ #%i %S;;\n"
+-    pos source verbose script_dir extra_args trash pos source;
++    pos source findlibdir verbose script_dir extra_args trash pos source;
+ 
+   List.iter (output_line oc) lines;
+ 
+@@ -550,6 +556,7 @@ let main () =
+       exit compilation_status
+ 
+ let _ =
++  Findlib.init ();
+   try main ()
+   with Failure s ->
+     eprintf "ocamlscript: %s\n%!" s;
+diff --git a/ocaml.ml b/ocaml.ml
+index a1824c6..b8f287e 100644
+--- a/ocaml.ml
++++ b/ocaml.ml
+@@ -14,7 +14,7 @@ let ocamlfind = ref "ocamlfind"
+ let packs = ref []         (* findlib packages *)
+ let sources = ref []       (* extra sources *)
+ let use_ocamllex = ref false (* preprocess with ocamllex before camlp4 *)
+-let use_camlp4 = ref true  (* by default camlp4 is used *)
++let use_camlp4 = ref false  (* by default camlp4 is not used *)
+ let use_ocamlc = ref false (* by default we want native code *)
+ let use_ocamlfind = ref false (* used only if necessary *)
+ let revised = ref false    (* use this to use the revised syntax *)

pkgs/development/tools/ocaml/ocamlscript/default.nix

@@ -0,0 +1,34 @@
+{ lib, stdenv, fetchFromGitHub, ocaml, findlib }:
+
+lib.throwIfNot (lib.versionAtLeast ocaml.version "4.08")
+  "ocamlscript is not available for OCaml ${ocaml.version}"
+
+stdenv.mkDerivation rec {
+  pname = "ocaml${ocaml.version}-ocamlscript";
+  version = "3.0.0";
+  src = fetchFromGitHub {
+    owner = "mjambon";
+    repo = "ocamlscript";
+    rev = "v${version}";
+    sha256 = "sha256:10xz8jknlmcgnf233nahd04q98ijnxpijhpvb8hl7sv94dgkvpql";
+  };
+
+  propagatedBuildInputs = [ ocaml findlib ];
+
+  patches = [ ./Makefile.patch ];
+
+  buildFlags = [ "PREFIX=$(out)" ];
+  installFlags = [ "PREFIX=$(out)" ];
+
+  preInstall = "mkdir -p $out/bin";
+  createFindlibDestdir = true;
+
+  meta = with lib; {
+    inherit (src.meta) homepage;
+    license = licenses.boost;
+    inherit (ocaml.meta) platforms;
+    description = "Natively-compiled OCaml scripts";
+    maintainers = [ maintainers.vbgl ];
+    mainProgram = "ocamlscript";
+  };
+}

pkgs/development/tools/ocaml/ocp-build/default.nix

@@ -0,0 +1,41 @@
+{ lib, stdenv, fetchFromGitHub, fetchpatch, ocaml, findlib, ncurses, cmdliner, re }:
+
+stdenv.mkDerivation rec {
+  pname = "ocaml${ocaml.version}-ocp-build";
+  version = "1.99.21";
+
+  src = fetchFromGitHub {
+    owner = "OCamlPro";
+    repo = "ocp-build";
+    rev = "v${version}";
+    sha256 = "1641xzik98c7xnjwxpacijd6d9jzx340fmdn6i372z8h554jjlg9";
+  };
+
+  patches = [
+    # Fix compilation with OCaml 4.12
+    (fetchpatch {
+      url = "https://github.com/OCamlPro/ocp-build/commit/104e4656ca6dba9edb03b62539c9f1e10abcaae8.patch";
+      sha256 = "0sbyi4acig9q8x1ky4hckfg5pm2nad6zasi51ravaf1spgl148c2";
+    })
+  ];
+
+  buildInputs = [ ocaml findlib cmdliner re ];
+  propagatedBuildInputs = [ ncurses ];
+  preInstall = "mkdir -p $out/bin";
+
+  meta = with lib; {
+    description = "A build tool for OCaml";
+    longDescription = ''
+      ocp-build is a build system for OCaml application, based on simple
+      descriptions of packages. ocp-build combines the descriptions of
+      packages, and optimize the parallel compilation of files depending on
+      the number of cores and the automatically-inferred dependencies
+      between source files.
+    '';
+    homepage = "https://www.typerex.org/ocp-build.html";
+    license = licenses.gpl3;
+    maintainers = [ maintainers.jirkamarsik ];
+    mainProgram = "ocp-build";
+    inherit (ocaml.meta) platforms;
+  };
+}

pkgs/development/tools/ocaml/ocp-indent/default.nix

@@ -0,0 +1,26 @@
+{ lib, fetchFromGitHub, buildDunePackage, cmdliner }:
+
+buildDunePackage rec {
+  version = "1.8.2";
+  pname = "ocp-indent";
+
+  useDune2 = true;
+
+  src = fetchFromGitHub {
+    owner = "OCamlPro";
+    repo = "ocp-indent";
+    rev = version;
+    sha256 = "sha256-IyvURw/6R0eKrnahV1fqLV0iIeypykrmxDbliECgbLc=";
+  };
+
+  minimumOCamlVersion = "4.02";
+
+  buildInputs = [ cmdliner ];
+
+  meta = with lib; {
+    homepage = "http://typerex.ocamlpro.com/ocp-indent.html";
+    description = "A customizable tool to indent OCaml code";
+    license = licenses.gpl3;
+    maintainers = [ maintainers.jirkamarsik ];
+  };
+}

pkgs/development/tools/ocaml/ocp-index/default.nix

@@ -0,0 +1,30 @@
+{ lib, fetchFromGitHub, buildDunePackage, cppo, ocp-indent, cmdliner, re }:
+
+buildDunePackage rec {
+  pname = "ocp-index";
+  version = "1.3.1";
+
+  useDune2 = true;
+
+  src = fetchFromGitHub {
+    owner = "OCamlPro";
+    repo = "ocp-index";
+    rev = version;
+    sha256 = "120w72fqymjp6ibicbp31jyx9yv34mdvgkr0zdfpzvfb7lgd8rc7";
+  };
+
+  strictDeps = true;
+
+  nativeBuildInputs = [ cppo ];
+  buildInputs = [ cmdliner re ];
+
+  propagatedBuildInputs = [ ocp-indent ];
+
+  meta = {
+    homepage = "https://www.typerex.org/ocp-index.html";
+    description = "A simple and light-weight documentation extractor for OCaml";
+    changelog = "https://github.com/OCamlPro/ocp-index/raw/${version}/CHANGES.md";
+    license = lib.licenses.lgpl3;
+    maintainers = with lib.maintainers; [ vbgl ];
+  };
+}

pkgs/development/tools/ocaml/ocsigen-i18n/default.nix

@@ -0,0 +1,30 @@
+{ lib, stdenv, fetchFromGitHub, ocamlPackages }:
+
+stdenv.mkDerivation rec {
+  pname = "ocsigen-i18n";
+  version = "3.7.0";
+
+  buildInputs = with ocamlPackages; [ ocaml findlib ppx_tools ];
+
+  dontStrip = true;
+
+  installPhase = ''
+    mkdir -p $out/bin
+    make bindir=$out/bin install
+  '';
+
+  src = fetchFromGitHub {
+    owner = "besport";
+    repo = "ocsigen-i18n";
+    rev = version;
+    sha256 = "sha256-PmdDyn+MUcNFrZpP/KLGQzdXUFRr+dYRAZjTZxHSeaw=";
+  };
+
+  meta = {
+    homepage = "https://github.com/besport/ocsigen-i18n";
+    description = "I18n made easy for web sites written with eliom";
+    license = lib.licenses.lgpl21;
+    maintainers = [ lib.maintainers.gal_bolle ];
+  };
+
+}

pkgs/development/tools/ocaml/omake/0.9.8.6-rc1.nix

@@ -0,0 +1,44 @@
+{lib, stdenv, fetchurl, makeWrapper, ocaml, ncurses}:
+let
+  pname = "omake";
+  version = "0.9.8.6-0.rc1";
+  webpage = "http://omake.metaprl.org";
+in
+
+if lib.versionAtLeast ocaml.version "4.06"
+then throw "${pname}-${version} is not available for OCaml ${ocaml.version}"
+else
+
+stdenv.mkDerivation {
+
+  name = "${pname}-${version}";
+
+  src = fetchurl {
+    url = "https://src.fedoraproject.org/repo/pkgs/ocaml-omake/${pname}-${version}.tar.gz/fe39a476ef4e33b7ba2ca77a6bcaded2/${pname}-${version}.tar.gz";
+    sha256 = "1sas02pbj56m7wi5vf3vqrrpr4ynxymw2a8ybvfj2dkjf7q9ii13";
+  };
+  patchFlags = [ "-p0" ];
+  patches = [ ./warn.patch ];
+
+  nativeBuildInputs = [ makeWrapper ];
+  buildInputs = [ ocaml ncurses ];
+
+  dontInstall = true;
+  buildPhase = ''
+    make bootstrap
+    make PREFIX=$out all
+    make PREFIX=$out install
+  '';
+#  prefixKey = "-prefix ";
+#
+#  configureFlags = if transitional then "--transitional" else "--strict";
+#
+#  buildFlags = [ "world.opt" ];
+
+  meta = {
+    description = "Omake build system";
+    homepage = webpage;
+    license = "GPL";
+    platforms = ocaml.meta.platforms or [];
+  };
+}

pkgs/development/tools/ocaml/omake/default.nix

@@ -0,0 +1,24 @@
+{ lib, stdenv, fetchurl, ocaml, ncurses }:
+
+stdenv.mkDerivation rec {
+
+  pname = "omake";
+  version = "0.10.3";
+
+  src = fetchurl {
+    url = "http://download.camlcity.org/download/${pname}-${version}.tar.gz";
+    sha256 = "07bdg1h5i7qnlv9xq81ad5hfypl10hxm771h4rjyl5cn8plhfcgz";
+  };
+
+  buildInputs = [ ocaml ncurses ];
+
+  meta = {
+    description = "A build system designed for scalability and portability";
+    homepage = "http://projects.camlcity.org/projects/omake.html";
+    license = with lib.licenses; [
+      mit /* scripts */
+      gpl2 /* program */
+    ];
+    inherit (ocaml.meta) platforms;
+  };
+}

pkgs/development/tools/ocaml/omake/warn.patch

@@ -0,0 +1,10 @@
+diff -p1 -aur ../omake-0.9.8.6.ori/lib/build/OCaml.om ./lib/build/OCaml.om
+--- ../omake-0.9.8.6.ori/lib/build/OCaml.om	2008-03-05 01:07:25.000000000 +0000
++++ ./lib/build/OCaml.om	2013-06-01 15:52:37.000000000 +0000
+@@ -178,3 +178,3 @@ declare OCAMLDEPFLAGS
+ public.OCAMLPPFLAGS  =
+-public.OCAMLFLAGS    = -warn-error A
++public.OCAMLFLAGS    =
+ public.OCAMLCFLAGS   = -g
+Seulement dans ./lib/build: OCaml.om~
+Seulement dans .: warn.patch

pkgs/development/tools/ocaml/opaline/default.nix

@@ -0,0 +1,28 @@
+{ lib, stdenv, fetchFromGitHub, ocamlPackages }:
+
+stdenv.mkDerivation rec {
+  version = "0.3.3";
+  pname = "opaline";
+
+  src = fetchFromGitHub {
+    owner = "jaapb";
+    repo = "opaline";
+    rev = "v${version}";
+    sha256 = "sha256-6htaiFIcRMUYWn0U7zTNfCyDaTgDEvPch2q57qzvND4=";
+  };
+
+  nativeBuildInputs = with ocamlPackages; [ ocaml findlib ocamlbuild ];
+  buildInputs = with ocamlPackages; [ opam-file-format ];
+
+  preInstall = "mkdir -p $out/bin";
+
+  installFlags = [ "PREFIX=$(out)" ];
+
+  meta = {
+    description = "OPAm Light INstaller Engine";
+    license = lib.licenses.mit;
+    maintainers = [ lib.maintainers.vbgl ];
+    inherit (src.meta) homepage;
+    inherit (ocamlPackages.ocaml.meta) platforms;
+  };
+}

pkgs/development/tools/ocaml/opam/1.2.2.nix

@@ -0,0 +1,93 @@
+{ stdenv, lib, fetchurl, makeWrapper,
+  ocaml, unzip, ncurses, curl, aspcud
+}:
+
+assert lib.versionAtLeast ocaml.version "3.12.1";
+
+let
+  srcs = {
+    cudf = fetchurl {
+      url = "https://gforge.inria.fr/frs/download.php/file/33593/cudf-0.7.tar.gz";
+      sha256 = "92c8a9ed730bbac73f3513abab41127d966c9b9202ab2aaffcd02358c030a701";
+    };
+    extlib = fetchurl {
+      url = "http://ocaml-extlib.googlecode.com/files/extlib-1.5.3.tar.gz";
+      sha256 = "c095eef4202a8614ff1474d4c08c50c32d6ca82d1015387785cf03d5913ec021";
+    };
+    ocaml_re = fetchurl {
+      url = "https://github.com/ocaml/ocaml-re/archive/ocaml-re-1.2.0.tar.gz";
+      sha256 = "a34dd9d6136731436a963bbab5c4bbb16e5d4e21b3b851d34887a3dec451999f";
+    };
+    ocamlgraph = fetchurl {
+      url = "http://ocamlgraph.lri.fr/download/ocamlgraph-1.8.5.tar.gz";
+      sha256 = "d167466435a155c779d5ec25b2db83ad851feb42ebc37dca8ffa345ddaefb82f";
+    };
+    dose3 = fetchurl {
+      url = "https://gforge.inria.fr/frs/download.php/file/34277/dose3-3.3.tar.gz";
+      sha256 = "8dc4dae9b1a81bb3a42abb283df785ba3eb00ade29b13875821c69f03e00680e";
+    };
+    cmdliner = fetchurl {
+      url = "https://erratique.ch/software/cmdliner/releases/cmdliner-0.9.7.tbz";
+      sha256 = "9c19893cffb5d3c3469ee0cce85e3eeeba17d309b33b9ace31aba06f68f0bf7a";
+    };
+    uutf = fetchurl {
+      url = "https://erratique.ch/software/uutf/releases/uutf-0.9.3.tbz";
+      sha256 = "1f364f89b1179e5182a4d3ad8975f57389d45548735d19054845e06a27107877";
+    };
+    jsonm = fetchurl {
+      url = "https://erratique.ch/software/jsonm/releases/jsonm-0.9.1.tbz";
+      sha256 = "3fd4dca045d82332da847e65e981d8b504883571d299a3f7e71447d46bc65f73";
+    };
+    opam = fetchurl {
+      url = "https://github.com/ocaml/opam/archive/1.2.2.zip";
+      sha256 = "c590ce55ae69ec74f46215cf16a156a02b23c5f3ecb22f23a3ad9ba3d91ddb6e";
+    };
+  };
+in stdenv.mkDerivation {
+  pname = "opam";
+  version = "1.2.2";
+
+  nativeBuildInputs = [ makeWrapper unzip ];
+  buildInputs = [ curl ncurses ocaml ];
+
+  src = srcs.opam;
+
+  postUnpack = ''
+    ln -sv ${srcs.cudf} $sourceRoot/src_ext/${srcs.cudf.name}
+    ln -sv ${srcs.extlib} $sourceRoot/src_ext/${srcs.extlib.name}
+    ln -sv ${srcs.ocaml_re} $sourceRoot/src_ext/${srcs.ocaml_re.name}
+    ln -sv ${srcs.ocamlgraph} $sourceRoot/src_ext/${srcs.ocamlgraph.name}
+    ln -sv ${srcs.dose3} $sourceRoot/src_ext/${srcs.dose3.name}
+    ln -sv ${srcs.cmdliner} $sourceRoot/src_ext/${srcs.cmdliner.name}
+    ln -sv ${srcs.uutf} $sourceRoot/src_ext/${srcs.uutf.name}
+    ln -sv ${srcs.jsonm} $sourceRoot/src_ext/${srcs.jsonm.name}
+  '';
+
+  preConfigure = ''
+    substituteInPlace ./src_ext/Makefile --replace "%.stamp: %.download" "%.stamp:"
+  '';
+
+  postConfigure = "make lib-ext";
+
+  # Dirty, but apparently ocp-build requires a TERM
+  makeFlags = ["TERM=screen"];
+
+  # change argv0 to "opam" as a workaround for
+  # https://github.com/ocaml/opam/issues/2142
+  postInstall = ''
+    mv $out/bin/opam $out/bin/.opam-wrapped
+    makeWrapper $out/bin/.opam-wrapped $out/bin/opam \
+      --argv0 "opam" \
+      --suffix PATH : ${aspcud}/bin:${unzip}/bin:${curl}/bin
+  '';
+
+  doCheck = false;
+
+  meta = with lib; {
+    description = "A package manager for OCaml";
+    homepage = "http://opam.ocamlpro.com/";
+    maintainers = [ maintainers.henrytill ];
+    platforms = platforms.all;
+    license = licenses.lgpl21Plus;
+  };
+}

pkgs/development/tools/ocaml/opam/default.nix

@@ -0,0 +1,136 @@
+{ stdenv, lib, fetchurl, makeWrapper, getconf,
+  ocaml, unzip, ncurses, curl, aspcud, bubblewrap
+}:
+
+assert lib.versionAtLeast ocaml.version "4.02.3";
+
+let
+  srcs = {
+    "0install-solver" = fetchurl {
+      url = "https://github.com/0install/0install/releases/download/v2.17/0install-v2.17.tbz";
+      sha256 = "08q95mzmf9pyyqs68ff52422f834hi313cxmypwrxmxsabcfa10p";
+    };
+    "cmdliner" = fetchurl {
+      url = "http://erratique.ch/software/cmdliner/releases/cmdliner-1.0.4.tbz";
+      sha256 = "1h04q0zkasd0mw64ggh4y58lgzkhg6yhzy60lab8k8zq9ba96ajw";
+    };
+    "cppo" = fetchurl {
+      url = "https://github.com/ocaml-community/cppo/releases/download/v1.6.7/cppo-v1.6.7.tbz";
+      sha256 = "17ajdzrnmnyfig3s6hinb56mcmhywbssxhsq32dz0v90dhz3wmfv";
+    };
+    "cudf" = fetchurl {
+      url = "https://github.com/ocaml/opam-source-archives/raw/main/cudf-0.9.tar.gz";
+      sha256 = "0771lwljqwwn3cryl0plny5a5dyyrj4z6bw66ha5n8yfbpcy8clr";
+    };
+    "dose3" = fetchurl {
+      url = "https://gitlab.com/irill/dose3/-/archive/5.0.1/dose3-5.0.1.tar.gz";
+      sha256 = "1mh6fv8qbf8xx4h2dc0dpv2lzygvikzjhw1idrknibbwsjw3jg9c";
+    };
+    "dune-local" = fetchurl {
+      url = "https://github.com/ocaml/dune/releases/download/2.9.0/dune-2.9.0.tbz";
+      sha256 = "07m476kgagpd6kzm3jq30yfxqspr2hychah0xfqs14z82zxpq8dv";
+    };
+    "extlib" = fetchurl {
+      url = "https://ygrek.org/p/release/ocaml-extlib/extlib-1.7.7.tar.gz";
+      sha256 = "1sxmzc1mx3kg62j8kbk0dxkx8mkf1rn70h542cjzrziflznap0s1";
+    };
+    "mccs" = fetchurl {
+      url = "https://github.com/AltGr/ocaml-mccs/archive/1.1+13.tar.gz";
+      sha256 = "05nnji9h8mss3hzjr5faid2v3xfr7rcv2ywmpcxxp28y6h2kv9gv";
+    };
+    "ocamlgraph" = fetchurl {
+      url = "https://github.com/backtracking/ocamlgraph/releases/download/2.0.0/ocamlgraph-2.0.0.tbz";
+      sha256 = "029692bvdz3hxpva9a2jg5w5381fkcw55ysdi8424lyyjxvjdzi0";
+    };
+    "opam-0install-cudf" = fetchurl {
+      url = "https://github.com/ocaml-opam/opam-0install-solver/releases/download/v0.4.2/opam-0install-cudf-v0.4.2.tbz";
+      sha256 = "10wma4hh9l8hk49rl8nql6ixsvlz3163gcxspay5fwrpbg51fmxr";
+    };
+    "opam-file-format" = fetchurl {
+      url = "https://github.com/ocaml/opam-file-format/archive/2.1.3.tar.gz";
+      sha256 = "1bqyrlsvmjf4gqzmzbiyja9m1ph30ic9i18x23p5ziymyylw2sfg";
+    };
+    "re" = fetchurl {
+      url = "https://github.com/ocaml/ocaml-re/releases/download/1.9.0/re-1.9.0.tbz";
+      sha256 = "1gas4ky49zgxph3870nffzkr6y41kkpqp4nj38pz1gh49zcf12aj";
+    };
+    "result" = fetchurl {
+      url = "https://github.com/janestreet/result/releases/download/1.5/result-1.5.tbz";
+      sha256 = "0cpfp35fdwnv3p30a06wd0py3805qxmq3jmcynjc3x2qhlimwfkw";
+    };
+    "seq" = fetchurl {
+      url = "https://github.com/c-cube/seq/archive/0.2.2.tar.gz";
+      sha256 = "1ck15v3pg8bacdg6d6iyp2jc3kgrzxk5jsgzx3287x2ycb897j53";
+    };
+    "stdlib-shims" = fetchurl {
+      url = "https://github.com/ocaml/stdlib-shims/releases/download/0.3.0/stdlib-shims-0.3.0.tbz";
+      sha256 = "0jnqsv6pqp5b5g7lcjwgd75zqqvcwcl5a32zi03zg1kvj79p5gxs";
+    };
+    opam = fetchurl {
+      url = "https://github.com/ocaml/opam/archive/2.1.2.zip";
+      sha256 = "0yq3dgx869016xrf65xv0glmqill1nk2ad12x3l36l70pn90rmyd";
+    };
+  };
+in stdenv.mkDerivation {
+  pname = "opam";
+  version = "2.1.2";
+
+  nativeBuildInputs = [ makeWrapper unzip ];
+  buildInputs = [ curl ncurses ocaml getconf ] ++ lib.optional stdenv.isLinux bubblewrap;
+
+  src = srcs.opam;
+
+  postUnpack = ''
+    ln -sv ${srcs."0install-solver"} $sourceRoot/src_ext/0install-solver.tbz
+    ln -sv ${srcs."cmdliner"} $sourceRoot/src_ext/cmdliner.tbz
+    ln -sv ${srcs."cppo"} $sourceRoot/src_ext/cppo.tbz
+    ln -sv ${srcs."cudf"} $sourceRoot/src_ext/cudf.tar.gz
+    ln -sv ${srcs."dose3"} $sourceRoot/src_ext/dose3.tar.gz
+    ln -sv ${srcs."dune-local"} $sourceRoot/src_ext/dune-local.tbz
+    ln -sv ${srcs."extlib"} $sourceRoot/src_ext/extlib.tar.gz
+    ln -sv ${srcs."mccs"} $sourceRoot/src_ext/mccs.tar.gz
+    ln -sv ${srcs."ocamlgraph"} $sourceRoot/src_ext/ocamlgraph.tbz
+    ln -sv ${srcs."opam-0install-cudf"} $sourceRoot/src_ext/opam-0install-cudf.tbz
+    ln -sv ${srcs."opam-file-format"} $sourceRoot/src_ext/opam-file-format.tar.gz
+    ln -sv ${srcs."re"} $sourceRoot/src_ext/re.tbz
+    ln -sv ${srcs."result"} $sourceRoot/src_ext/result.tbz
+    ln -sv ${srcs."seq"} $sourceRoot/src_ext/seq.tar.gz
+    ln -sv ${srcs."stdlib-shims"} $sourceRoot/src_ext/stdlib-shims.tbz
+  '';
+
+  patches = [ ./opam-shebangs.patch ];
+
+  preConfigure = ''
+    substituteInPlace ./src_ext/Makefile --replace "%.stamp: %.download" "%.stamp:"
+    patchShebangs src/state/shellscripts
+  '';
+
+  postConfigure = "make lib-ext";
+
+  # Dirty, but apparently ocp-build requires a TERM
+  makeFlags = ["TERM=screen"];
+
+  outputs = [ "out" "installer" ];
+  setOutputFlags = false;
+
+  # change argv0 to "opam" as a workaround for
+  # https://github.com/ocaml/opam/issues/2142
+  postInstall = ''
+    mv $out/bin/opam $out/bin/.opam-wrapped
+    makeWrapper $out/bin/.opam-wrapped $out/bin/opam \
+      --argv0 "opam" \
+      --suffix PATH : ${aspcud}/bin:${unzip}/bin:${curl}/bin:${lib.optionalString stdenv.isLinux "${bubblewrap}/bin:"}${getconf}/bin \
+      --set OPAM_USER_PATH_RO /run/current-system/sw/bin:/nix/
+    $out/bin/opam-installer --prefix=$installer opam-installer.install
+  '';
+
+  doCheck = false;
+
+  meta = with lib; {
+    description = "A package manager for OCaml";
+    homepage = "https://opam.ocaml.org/";
+    maintainers = [ maintainers.henrytill maintainers.marsam ];
+    platforms = platforms.all;
+  };
+}
+# Generated by: ./opam.nix.pl -v 2.1.2 -p opam-shebangs.patch

pkgs/development/tools/ocaml/opam/installer.nix

@@ -0,0 +1,17 @@
+{ lib, unzip, opam, ocamlPackages }:
+
+ocamlPackages.buildDunePackage {
+  pname = "opam-installer";
+
+  useDune2 = true;
+
+  inherit (opam) version src;
+  nativeBuildInputs = [ unzip ];
+
+  configureFlags = [ "--disable-checks" "--prefix=$out" ];
+  buildInputs = with ocamlPackages; [ opam-format cmdliner ];
+
+  meta = opam.meta // {
+    description = "Handle (un)installation from opam install files";
+  };
+}

pkgs/development/tools/ocaml/opam/opam-shebangs.patch

@@ -0,0 +1,131 @@
+diff --git a/src/client/opamInitDefaults.ml b/src/client/opamInitDefaults.ml
+index eca13a7c..1fd66f43 100644
+--- a/src/client/opamInitDefaults.ml
++++ b/src/client/opamInitDefaults.ml
+@@ -35,14 +35,18 @@ let eval_variables = [
+ let os_filter os =
+   FOp (FIdent ([], OpamVariable.of_string "os", None), `Eq, FString os)
+ 
++let os_distribution_filter distro =
++  FOp (FIdent ([], OpamVariable.of_string "os-distribution", None), `Eq, FString distro)
++
+ let linux_filter = os_filter "linux"
+ let macos_filter = os_filter "macos"
+ let openbsd_filter = os_filter "openbsd"
+ let freebsd_filter = os_filter "freebsd"
+ let not_open_free_bsd_filter =
+   FNot (FOr (openbsd_filter,  freebsd_filter))
+ let win32_filter = os_filter "win32"
+ let sandbox_filter = FOr (linux_filter, macos_filter)
++let nixos_filter = os_distribution_filter "nixos"
+ 
+ let gpatch_filter = FOr (openbsd_filter, freebsd_filter)
+ let patch_filter = FNot gpatch_filter
+@@ -50,6 +54,11 @@ let wrappers ~sandboxing () =
+     CString t, None;
+   ] in
+   let w = OpamFile.Wrappers.empty in
++  let w = { w with
++            OpamFile.Wrappers.
++            pre_build = [[CString "%{hooks}%/shebangs.sh", None], Some nixos_filter];
++          }
++  in
+   if sandboxing then
+     { w with
+       OpamFile.Wrappers.
+@@ -113,6 +122,7 @@ let required_tools ~sandboxing () =
+ let init_scripts () = [
+   ("sandbox.sh", OpamScript.bwrap), Some bwrap_filter;
+   ("sandbox.sh", OpamScript.sandbox_exec), Some macos_filter;
++  ("shebangs.sh", OpamScript.patch_shebangs), Some nixos_filter;
+ ]
+ 
+ module I = OpamFile.InitConfig
+diff --git a/src/state/opamScript.mli b/src/state/opamScript.mli
+index 03449970..83de0b53 100644
+--- a/src/state/opamScript.mli
++++ b/src/state/opamScript.mli
+@@ -20,3 +20,4 @@ val env_hook : string
+ val env_hook_zsh : string
+ val env_hook_csh : string
+ val env_hook_fish : string
++val patch_shebangs : string
+diff --git a/src/state/shellscripts/patch_shebangs.sh b/src/state/shellscripts/patch_shebangs.sh
+new file mode 100755
+index 00000000..3ea84e2d
+--- /dev/null
++++ b/src/state/shellscripts/patch_shebangs.sh
+@@ -0,0 +1,73 @@
++#!/usr/bin/env bash
++# This setup hook causes the fixup phase to rewrite all script
++# interpreter file names (`#!  /path') to paths found in $PATH.  E.g.,
++# /bin/sh will be rewritten to /nix/store/<hash>-some-bash/bin/sh.
++# /usr/bin/env gets special treatment so that ".../bin/env python" is
++# rewritten to /nix/store/<hash>/bin/python.  Interpreters that are
++# already in the store are left untouched.
++
++header() { echo "$1"; }
++stopNest() { true; }
++
++fixupOutputHooks+=('if [ -z "${dontPatchShebangs-}" -a -e "$prefix" ]; then patchShebangs "$prefix"; fi')
++
++patchShebangs() {
++    local dir="$1"
++    header "patching script interpreter paths in $dir"
++    local f
++    local oldPath
++    local newPath
++    local arg0
++    local args
++    local oldInterpreterLine
++    local newInterpreterLine
++
++    find "$dir" -type f -perm -0100 | while read f; do
++        if [ "$(head -1 "$f" | head -c+2)" != '#!' ]; then
++            # missing shebang => not a script
++            continue
++        fi
++
++        oldInterpreterLine=$(head -1 "$f" | tail -c+3)
++        read -r oldPath arg0 args <<< "$oldInterpreterLine"
++
++        if $(echo "$oldPath" | grep -q "/bin/env$"); then
++            # Check for unsupported 'env' functionality:
++            # - options: something starting with a '-'
++            # - environment variables: foo=bar
++            if $(echo "$arg0" | grep -q -- "^-.*\|.*=.*"); then
++                echo "unsupported interpreter directive \"$oldInterpreterLine\" (set dontPatchShebangs=1 and handle shebang patching yourself)"
++                exit 1
++            fi
++            newPath="$(command -v "$arg0" || true)"
++        else
++            if [ "$oldPath" = "" ]; then
++                # If no interpreter is specified linux will use /bin/sh. Set
++                # oldpath="/bin/sh" so that we get /nix/store/.../sh.
++                oldPath="/bin/sh"
++            fi
++            newPath="$(command -v "$(basename "$oldPath")" || true)"
++            args="$arg0 $args"
++        fi
++
++        # Strip trailing whitespace introduced when no arguments are present
++        newInterpreterLine="$(echo "$newPath $args" | sed 's/[[:space:]]*$//')"
++
++        if [ -n "$oldPath" -a "${oldPath:0:${#NIX_STORE}}" != "$NIX_STORE" ]; then
++            if [ -n "$newPath" -a "$newPath" != "$oldPath" ]; then
++                echo "$f: interpreter directive changed from \"$oldInterpreterLine\" to \"$newInterpreterLine\""
++                # escape the escape chars so that sed doesn't interpret them
++                escapedInterpreterLine=$(echo "$newInterpreterLine" | sed 's|\\|\\\\|g')
++                # Preserve times, see: https://github.com/NixOS/nixpkgs/pull/33281
++                touch -r "$f" "$f.timestamp"
++                sed -i -e "1 s|.*|#\!$escapedInterpreterLine|" "$f"
++                touch -r "$f.timestamp" "$f"
++                rm "$f.timestamp"
++            fi
++        fi
++    done
++
++    stopNest
++}
++
++patchShebangs .

pkgs/development/tools/ocaml/opam/opam.nix.pl

@@ -0,0 +1,132 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings qw<all>;
+use Getopt::Std;
+
+my $gencmd = "# Generated by: " . join(" ", $0, @ARGV) . "\n";
+
+our $opt_v;
+our $opt_p;
+our $opt_r;
+our $opt_t;
+getopts "v:p:t:r:";
+
+my $OPAM_RELEASE = $opt_v // "2.0.0";
+my $OPAM_TAG = $opt_t // $OPAM_RELEASE;
+my $OPAM_GITHUB_REPO = $opt_r // "ocaml/opam";
+my $OPAM_RELEASE_URL = "https://github.com/$OPAM_GITHUB_REPO/archive/$OPAM_TAG.zip";
+my $OPAM_RELEASE_SHA256 = `nix-prefetch-url \Q$OPAM_RELEASE_URL\E`;
+chomp $OPAM_RELEASE_SHA256;
+
+my $OPAM_BASE_URL = "https://raw.githubusercontent.com/$OPAM_GITHUB_REPO/$OPAM_TAG";
+my $OPAM_OPAM = `curl -L --url \Q$OPAM_BASE_URL\E/opam-devel.opam`;
+my($OCAML_MIN_VERSION) = $OPAM_OPAM =~ /^  "ocaml" {>= "(.*)"}$/m
+  or die "could not parse ocaml version bound\n";
+
+print <<"EOF";
+{ stdenv, lib, fetchurl, makeWrapper, getconf,
+  ocaml, unzip, ncurses, curl, aspcud, bubblewrap
+}:
+
+assert lib.versionAtLeast ocaml.version "$OCAML_MIN_VERSION";
+
+let
+  srcs = {
+EOF
+
+my %urls = ();
+my %md5s = ();
+
+open(SOURCES, "-|", "curl", "-L", "--url", "$OPAM_BASE_URL/src_ext/Makefile.sources");
+while (<SOURCES>) {
+  if (/^URL_(?!PKG_)([-\w]+)\s*=\s*(\S+)$/) {
+    $urls{$1} = $2;
+  } elsif (/^MD5_(?!PKG_)([-\w]+)\s*=\s*(\S+)$/) {
+    $md5s{$1} = $2;
+  }
+}
+for my $src (sort keys %urls) {
+  my ($sha256,$store_path) = split /\n/, `nix-prefetch-url --print-path \Q$urls{$src}\E`;
+  system "echo \Q$md5s{$src}\E' *'\Q$store_path\E | md5sum -c 1>&2";
+  die "md5 check failed for $urls{$src}\n" if $?;
+  print <<"EOF";
+    "$src" = fetchurl {
+      url = "$urls{$src}";
+      sha256 = "$sha256";
+    };
+EOF
+}
+
+print <<"EOF";
+    opam = fetchurl {
+      url = "$OPAM_RELEASE_URL";
+      sha256 = "$OPAM_RELEASE_SHA256";
+    };
+  };
+in stdenv.mkDerivation {
+  pname = "opam";
+  version = "$OPAM_RELEASE";
+
+  nativeBuildInputs = [ makeWrapper unzip ];
+  buildInputs = [ curl ncurses ocaml getconf ] ++ lib.optional stdenv.isLinux bubblewrap;
+
+  src = srcs.opam;
+
+  postUnpack = ''
+EOF
+for my $src (sort keys %urls) {
+  my($ext) = $urls{$src} =~ /(\.(?:t(?:ar\.|)|)(?:gz|bz2?))$/
+    or die "could not find extension for $urls{$src}\n";
+  print <<"EOF";
+    ln -sv \${srcs."$src"} \$sourceRoot/src_ext/$src$ext
+EOF
+}
+print <<'EOF';
+  '';
+
+EOF
+if (defined $opt_p) {
+  print "  patches = [ ";
+  for my $patch (split /[, ]/, $opt_p) {
+    $patch =~ s/^(?=[^\/]*$)/.\//;
+    print "$patch ";
+  }
+  print "];\n\n";
+}
+print <<'EOF';
+  preConfigure = ''
+    substituteInPlace ./src_ext/Makefile --replace "%.stamp: %.download" "%.stamp:"
+    patchShebangs src/state/shellscripts
+  '';
+
+  postConfigure = "make lib-ext";
+
+  # Dirty, but apparently ocp-build requires a TERM
+  makeFlags = ["TERM=screen"];
+
+  outputs = [ "out" "installer" ];
+  setOutputFlags = false;
+
+  # change argv0 to "opam" as a workaround for
+  # https://github.com/ocaml/opam/issues/2142
+  postInstall = ''
+    mv $out/bin/opam $out/bin/.opam-wrapped
+    makeWrapper $out/bin/.opam-wrapped $out/bin/opam \
+      --argv0 "opam" \
+      --suffix PATH : ${aspcud}/bin:${unzip}/bin:${curl}/bin:${lib.optionalString stdenv.isLinux "${bubblewrap}/bin:"}${getconf}/bin \
+      --set OPAM_USER_PATH_RO /run/current-system/sw/bin:/nix/
+    $out/bin/opam-installer --prefix=$installer opam-installer.install
+  '';
+
+  doCheck = false;
+
+  meta = with lib; {
+    description = "A package manager for OCaml";
+    homepage = "https://opam.ocaml.org/";
+    maintainers = [ maintainers.henrytill maintainers.marsam ];
+    platforms = platforms.all;
+  };
+}
+EOF
+print $gencmd;

pkgs/development/tools/ocaml/utop/default.nix

@@ -0,0 +1,76 @@
+{ lib, stdenv, fetchurl, ocaml, findlib
+, lambda-term, cppo, makeWrapper, buildDunePackage
+}:
+
+buildDunePackage rec {
+  pname = "utop";
+  version = "2.9.1";
+
+  useDune2 = true;
+
+  minimalOCamlVersion = "4.03";
+
+  src = fetchurl {
+    url = "https://github.com/ocaml-community/utop/releases/download/${version}/utop-${version}.tbz";
+    sha256 = "sha256-6TQxLYN/qjTABZuK6rp+daCSNWyJIXzB8q2QpZeBwaY=";
+  };
+
+  nativeBuildInputs = [ makeWrapper cppo ];
+
+  propagatedBuildInputs = [ lambda-term ];
+
+  postFixup =
+   let
+     path = "etc/utop/env";
+
+     # derivation of just runtime deps so env vars created by
+     # setup-hooks can be saved for use at runtime
+     runtime = stdenv.mkDerivation {
+       pname = "utop-runtime-env";
+       inherit version;
+
+       buildInputs = [ findlib ] ++ propagatedBuildInputs;
+
+       dontUnpack = true;
+
+       installPhase = ''
+         mkdir -p "$out"/${path}
+         for e in OCAMLPATH CAML_LD_LIBRARY_PATH; do
+           [[ -v "$e" ]] || continue
+           printf %s "''${!e}" > "$out"/${path}/$e
+         done
+       '';
+     };
+
+     get = key: ''$(cat "${runtime}/${path}/${key}")'';
+   in ''
+   for prog in "$out"/bin/*
+   do
+
+    # Note: wrapProgram by default calls 'exec -a $0 ...', but this
+    # breaks utop on Linux with OCaml 4.04, and is disabled with
+    # '--argv0 ""' flag. See https://github.com/NixOS/nixpkgs/issues/24496
+    wrapProgram "$prog" \
+      --argv0 "" \
+      --prefix CAML_LD_LIBRARY_PATH ":" "${get "CAML_LD_LIBRARY_PATH"}" \
+      --prefix OCAMLPATH ":" "${get "OCAMLPATH"}" \
+      --prefix OCAMLPATH ":" $(unset OCAMLPATH; addOCamlPath "$out"; printf %s "$OCAMLPATH") \
+      --add-flags "-I ${findlib}/lib/ocaml/${lib.getVersion ocaml}/site-lib"
+   done
+   '';
+
+  meta = {
+    description = "Universal toplevel for OCaml";
+    longDescription = ''
+    utop is an improved toplevel for OCaml. It can run in a terminal or in Emacs. It supports line edition, history, real-time and context sensitive completion, colors, and more.
+
+    It integrates with the tuareg mode in Emacs.
+    '';
+    homepage = "https://github.com/diml/utop";
+    license = lib.licenses.bsd3;
+    platforms = ocaml.meta.platforms or [];
+    maintainers = [
+      lib.maintainers.gal_bolle
+    ];
+  };
+}