diff --git a/pkgs/tools/audio/kaldi/default.nix b/pkgs/tools/audio/kaldi/default.nix
index 79da94f72435..777a7535a10c 100644
--- a/pkgs/tools/audio/kaldi/default.nix
+++ b/pkgs/tools/audio/kaldi/default.nix
@@ -3,7 +3,6 @@
 , openblas
 , blas
 , lapack
-, openfst
 , icu
 , cmake
 , pkg-config
@@ -11,27 +10,23 @@
 , git
 , python3
 , Accelerate
+, _experimental-update-script-combinators
+, common-updater-scripts
+, ripgrep
+, unstableGitUpdater
+, writeShellScript
 }:
 
 assert blas.implementation == "openblas" && lapack.implementation == "openblas";
-let
-  # rev from https://github.com/kaldi-asr/kaldi/blob/master/cmake/third_party/openfst.cmake
-  openfst = fetchFromGitHub {
-    owner = "kkm000";
-    repo = "openfst";
-    rev = "338225416178ac36b8002d70387f5556e44c8d05";
-    sha256 = "sha256-MGEUuw7ex+WcujVdxpO2Bf5sB6Z0edcAeLGqW/Lo1Hs=";
-  };
-in
-stdenv.mkDerivation {
+stdenv.mkDerivation (finalAttrs: {
   pname = "kaldi";
-  version = "unstable-2022-09-26";
+  version = "unstable-2023-05-02";
 
   src = fetchFromGitHub {
     owner = "kaldi-asr";
     repo = "kaldi";
-    rev = "f6f4ccaf213f0fe8b26e633a7dc0c802150626a0";
-    sha256 = "sha256-ybW2J4lWf6YaQGZZvxEVDUMAg84DC17W+yX6ZsuBDac=";
+    rev = "71f38e62cad01c3078555bfe78d0f3a527422d75";
+    sha256 = "sha256-2xm0F80cjovy/G9Ytq/iwa1eexZk0mromv6PPuNIT8U=";
   };
 
   cmakeFlags = [
@@ -39,42 +34,11 @@ stdenv.mkDerivation {
     "-DBUILD_SHARED_LIBS=on"
     "-DBLAS_LIBRARIES=-lblas"
     "-DLAPACK_LIBRARIES=-llapack"
+    "-DFETCHCONTENT_SOURCE_DIR_OPENFST:PATH=${finalAttrs.passthru.sources.openfst}"
   ];
 
-  enableParallelBuilding = true;
-
-  preConfigure = ''
-    mkdir bin
-    cat > bin/git <<'EOF'
-    #!${stdenv.shell}
-    if [[ "$1" == "--version" ]]; then
-      # cmake checks this
-      ${git}/bin/git --version
-    elif [[ "$1" == "clone" ]]; then
-      # mock this call:
-
-      # https://github.com/kaldi-asr/kaldi/blob/c9d8b9ad3fef89237ba5517617d977b7d70a7ed5/cmake/third_party/openfst.cmake#L5
-      cp -r ${openfst} ''${@: -1}
-      chmod -R +w ''${@: -1}
-    elif [[ "$1" == "rev-list" ]]; then
-      # fix up this call:
-      # https://github.com/kaldi-asr/kaldi/blob/c9d8b9ad3fef89237ba5517617d977b7d70a7ed5/cmake/VersionHelper.cmake#L8
-      echo 0
-    elif [[ "$1" == "rev-parse" ]]; then
-      echo ${openfst.rev}
-      echo 0
-    fi
-    true
-    EOF
-    chmod +x bin/git
-    export PATH=$(pwd)/bin:$PATH
-  '';
-
-  outputs = [ "out" "dev" ];
-
   buildInputs = [
     openblas
-    openfst
     icu
   ] ++ lib.optionals stdenv.isDarwin [
     Accelerate
@@ -86,11 +50,46 @@ stdenv.mkDerivation {
     python3
   ];
 
+  preConfigure = ''
+    cmakeFlagsArray+=(
+      # Extract version without the need for git.
+      # https://github.com/kaldi-asr/kaldi/blob/71f38e62cad01c3078555bfe78d0f3a527422d75/cmake/VersionHelper.cmake
+      # Patch number is not actually used by default so we can just ignore it.
+      # https://github.com/kaldi-asr/kaldi/blob/71f38e62cad01c3078555bfe78d0f3a527422d75/CMakeLists.txt#L214
+      "-DKALDI_VERSION=$(cat src/.version)"
+    )
+  '';
+
   postInstall = ''
     mkdir -p $out/share/kaldi
     cp -r ../egs $out/share/kaldi
   '';
 
+  passthru = {
+    sources = {
+      # rev from https://github.com/kaldi-asr/kaldi/blob/master/cmake/third_party/openfst.cmake
+      openfst = fetchFromGitHub {
+        owner = "kkm000";
+        repo = "openfst";
+        rev = "338225416178ac36b8002d70387f5556e44c8d05";
+        hash = "sha256-MGEUuw7ex+WcujVdxpO2Bf5sB6Z0edcAeLGqW/Lo1Hs=";
+      };
+    };
+
+    updateScript =
+      let
+        updateSource = unstableGitUpdater {};
+        updateOpenfst = writeShellScript "update-openfst" ''
+          hash=$(${ripgrep}/bin/rg --multiline --pcre2 --only-matching 'FetchContent_Declare\(\s*openfst[^)]*GIT_TAG\s*([0-9a-f]{40})' --replace '$1' "${finalAttrs.src}/cmake/third_party/openfst.cmake")
+          ${common-updater-scripts}/bin/update-source-version kaldi.sources.openfst "$hash" --source-key=out "--version-key=rev"
+        '';
+      in
+      _experimental-update-script-combinators.sequence [
+        updateSource
+        updateOpenfst
+      ];
+    };
+
   meta = with lib; {
     description = "Speech Recognition Toolkit";
     homepage = "https://kaldi-asr.org";
@@ -98,4 +97,4 @@ stdenv.mkDerivation {
     maintainers = with maintainers; [ mic92 ];
     platforms = platforms.unix;
   };
-}
+})