diff --git a/pkgs/development/libraries/md4c/default.nix b/pkgs/development/libraries/md4c/default.nix
new file mode 100644
index 000000000000..a711ecb7c768
--- /dev/null
+++ b/pkgs/development/libraries/md4c/default.nix
@@ -0,0 +1,59 @@
+{ lib
+, stdenv
+, fetchFromGitHub
+, cmake
+, pkg-config
+}:
+
+stdenv.mkDerivation rec {
+  pname = "md4c";
+  version = "0.4.7";
+
+  src = fetchFromGitHub {
+    owner = "mity";
+    repo = pname;
+    rev = "release-${version}";
+    hash = "sha256-nfMXUP1wu3ifn1QVTO/+XcfFRsThG8PlmYRv+b8AYlQ=";
+  };
+
+  nativeBuildInputs = [
+    cmake
+    pkg-config
+  ];
+
+  meta = with lib; {
+    homepage = "https://github.com/mity/md4c";
+    description = "Markdown parser made in C";
+    longDescription = ''
+      MD4C is Markdown parser implementation in C, with the following features:
+
+      - Compliance: Generally, MD4C aims to be compliant to the latest version
+        of CommonMark specification. Currently, we are fully compliant to
+        CommonMark 0.29.
+      - Extensions: MD4C supports some commonly requested and accepted
+        extensions. See below.
+      - Performance: MD4C is very fast.
+      - Compactness: MD4C parser is implemented in one source file and one
+        header file. There are no dependencies other than standard C library.
+      - Embedding: MD4C parser is easy to reuse in other projects, its API is
+        very straightforward: There is actually just one function, md_parse().
+      - Push model: MD4C parses the complete document and calls few callback
+        functions provided by the application to inform it about a start/end of
+        every block, a start/end of every span, and with any textual contents.
+      - Portability: MD4C builds and works on Windows and POSIX-compliant
+        OSes. (It should be simple to make it run also on most other platforms,
+        at least as long as the platform provides C standard library, including
+        a heap memory management.)
+      - Encoding: MD4C by default expects UTF-8 encoding of the input
+        document. But it can be compiled to recognize ASCII-only control
+        characters (i.e. to disable all Unicode-specific code), or (on Windows)
+        to expect UTF-16 (i.e. what is on Windows commonly called just
+        "Unicode"). See more details below.
+      - Permissive license: MD4C is available under the MIT license.
+    '';
+    license = licenses.mit;
+    maintainers = with maintainers; [ AndersonTorres ];
+    platforms = platforms.all;
+  };
+}
+# TODO: enable tests (needs Python)
diff --git a/pkgs/development/tools/castxml/default.nix b/pkgs/development/tools/castxml/default.nix
index ff47bd0e9f36..f3d9b74181aa 100644
--- a/pkgs/development/tools/castxml/default.nix
+++ b/pkgs/development/tools/castxml/default.nix
@@ -1,52 +1,69 @@
-{ lib, stdenv, fetchFromGitHub
-, python3Packages
+{ lib
+, stdenv
+, fetchFromGitHub
+, clang-unwrapped
 , cmake
-, llvmPackages
-, libffi, libxml2, zlib
-, withMan ? true
+, libclang
+, libffi
+, libxml2
+, llvm
+, sphinx
+, zlib
+, withManual ? true
+, withHTML ? true
 }:
-stdenv.mkDerivation rec {
 
-  pname   = "CastXML";
-  version = "0.3.4";
+stdenv.mkDerivation rec {
+  pname = "CastXML";
+  version = "0.4.3";
 
   src = fetchFromGitHub {
-    owner  = pname;
-    repo   = pname;
-    rev    = "v${version}";
-    sha256 = "0ypj67xrgj228myp7l1gsjw1ja97q68nmj98dsd33srmiayqraj4";
+    owner = pname;
+    repo = pname;
+    rev = "v${version}";
+    hash = "sha256-MschwCEkZrZmNgr8a1ocdukjXzHbXl2gmkPmygJaA6k=";
   };
 
-  nativeBuildInputs = [ cmake ] ++ lib.optionals withMan [ python3Packages.sphinx ];
-
-  clangVersion = lib.getVersion llvmPackages.clang;
+  nativeBuildInputs = [
+    cmake
+    llvm
+  ] ++ lib.optionals (withManual || withHTML) [
+    sphinx
+  ];
 
   cmakeFlags = [
-    "-DCLANG_RESOURCE_DIR=${llvmPackages.clang-unwrapped}/lib/clang/${clangVersion}/"
-    "-DSPHINX_MAN=${if withMan then "ON" else "OFF"}"
+    "-DCLANG_RESOURCE_DIR=${clang-unwrapped}/lib/clang/${lib.getVersion clang-unwrapped}/"
+    "-DSPHINX_HTML=${if withHTML then "ON" else "OFF"}"
+    "-DSPHINX_MAN=${if withManual then "ON" else "OFF"}"
   ];
 
   buildInputs = [
-    llvmPackages.clang-unwrapped
-    llvmPackages.llvm
-    libffi libxml2 zlib
+    clang-unwrapped
+    libffi
+    libxml2
+    zlib
   ];
 
-  propagatedBuildInputs = [ llvmPackages.libclang ];
+  propagatedBuildInputs = [
+    libclang
+  ];
 
   # 97% tests passed, 97 tests failed out of 2881
   # mostly because it checks command line and nix append -isystem and all
   doCheck = false;
+  # -E exclude 4 tests based on names
+  # see https://github.com/CastXML/CastXML/issues/90
   checkPhase = ''
-    # -E exclude 4 tests based on names
-    # see https://github.com/CastXML/CastXML/issues/90
+    runHook preCheck
     ctest -E 'cmd.cc-(gnu|msvc)-((c-src-c)|(src-cxx))-cmd'
+    runHook postCheck
   '';
 
   meta = with lib; {
     homepage = "https://github.com/CastXML/CastXML";
+    description = "C-family Abstract Syntax Tree XML Output";
     license = licenses.asl20;
-    description = "Abstract syntax tree XML output tool";
+    maintainers = with maintainers; [ AndersonTorres ];
     platforms = platforms.unix;
   };
 }
diff --git a/pkgs/tools/text/m2r/default.nix b/pkgs/tools/text/m2r/default.nix
new file mode 100644
index 000000000000..f6dda712d0b9
--- /dev/null
+++ b/pkgs/tools/text/m2r/default.nix
@@ -0,0 +1,32 @@
+{ lib
+, buildPythonApplication
+, fetchFromGitHub
+, docutils
+, mistune
+, pygments
+}:
+
+buildPythonApplication rec {
+  pname = "m2r";
+  version = "0.2.1";
+
+  src = fetchFromGitHub {
+    owner = "miyakogi";
+    repo = pname;
+    rev = "v${version}";
+    hash = "sha256-JNLPEXMoiISh4RnKP+Afj9/PJp9Lrx9UYHsfuGAL7uI=";
+  };
+
+  buildInputs = [
+    docutils
+    mistune
+    pygments
+  ];
+
+  meta = with lib; {
+    homepage = "https://github.com/miyakogi/m2r";
+    description = "Markdown-to-RestructuredText converter";
+    license = licenses.mit;
+    maintainers = with maintainers; [ AndersonTorres ];
+  };
+}
diff --git a/pkgs/tools/text/xml/xmldiff/default.nix b/pkgs/tools/text/xml/xmldiff/default.nix
new file mode 100644
index 000000000000..5814435e111b
--- /dev/null
+++ b/pkgs/tools/text/xml/xmldiff/default.nix
@@ -0,0 +1,41 @@
+{ lib
+, buildPythonApplication
+, fetchFromGitHub
+, lxml
+, six
+}:
+
+buildPythonApplication rec {
+  pname = "xmldiff";
+  version = "2.4";
+
+  src = fetchFromGitHub {
+    owner = "Shoobx";
+    repo = pname;
+    rev = version;
+    hash = "sha256-xqudHYfwOce2C0pcFzId0JDIIC6R5bllmVKsH+CvTdE=";
+  };
+
+  buildInputs = [
+    lxml
+    six
+  ];
+
+  meta = with lib; {
+    homepage = "https://xmldiff.readthedocs.io/en/stable/";
+    description = "A library and command line utility for diffing xml";
+    longDescription = ''
+      xmldiff is a library and a command-line utility for making diffs out of
+      XML. This may seem like something that doesn't need a dedicated utility,
+      but change detection in hierarchical data is very different from change
+      detection in flat data. XML type formats are also not only used for
+      computer readable data, it is also often used as a format for hierarchical
+      data that can be rendered into human readable formats. A traditional diff
+      on such a format would tell you line by line the differences, but this
+      would not be be readable by a human. xmldiff provides tools to make human
+      readable diffs in those situations.
+    '';
+    license = licenses.mit;
+    maintainers = with maintainers; [ AndersonTorres ];
+  };
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 06c862e9f0b6..9b012e8990f2 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -190,7 +190,10 @@ in
 
   castget = callPackage ../applications/networking/feedreaders/castget { };
 
-  castxml = callPackage ../development/tools/castxml { };
+  castxml = callPackage ../development/tools/castxml {
+    inherit (llvmPackages) clang-unwrapped libclang llvm;
+    inherit (python3Packages) sphinx;
+  };
 
   cen64 = callPackage ../misc/emulators/cen64 { };
 
@@ -5835,6 +5838,8 @@ in
 
   mcfly = callPackage ../tools/misc/mcfly { };
 
+  m2r = python3Packages.callPackage ../tools/text/m2r { };
+
   mdbook = callPackage ../tools/text/mdbook {
     inherit (darwin.apple_sdk.frameworks) CoreServices;
   };
@@ -9305,6 +9310,8 @@ in
 
   xml2 = callPackage ../tools/text/xml/xml2 { };
 
+  xmldiff = python3Packages.callPackage ../tools/text/xml/xmldiff { };
+
   xmlformat = callPackage ../tools/text/xml/xmlformat { };
 
   xmlroff = callPackage ../tools/typesetting/xmlroff { };
@@ -16052,6 +16059,8 @@ in
 
   mdctags = callPackage ../development/tools/misc/mdctags { };
 
+  md4c = callPackage ../development/libraries/md4c { };
+
   mdds = callPackage ../development/libraries/mdds { };
 
   mediastreamer = callPackage ../development/libraries/mediastreamer { };