diff --git a/.github/autobump.txt b/.github/autobump.txt
index 2a96adceaec49..cfa5360af23c4 100644
--- a/.github/autobump.txt
+++ b/.github/autobump.txt
@@ -1736,6 +1736,7 @@ libtrng
 libucl
 libultrahdr
 libunibreak
+libunicode
 libuninameslist
 libunistring
 libunwind
diff --git a/Formula/lib/libunicode.rb b/Formula/lib/libunicode.rb
new file mode 100644
index 0000000000000..eff8e6eed7ae8
--- /dev/null
+++ b/Formula/lib/libunicode.rb
@@ -0,0 +1,72 @@
+class Libunicode < Formula
+  desc "Modern C++20 Unicode library"
+  homepage "https://github.com/contour-terminal/libunicode"
+  url "https://github.com/contour-terminal/libunicode/archive/refs/tags/v0.6.0.tar.gz"
+  sha256 "0c217f8264000f1b8c36e78969cb9cf91ac97de937cc141ab78e6b1ad7f404ef"
+  license "Apache-2.0"
+
+  bottle do
+    sha256 cellar: :any,                 arm64_sequoia: "2e51dbe77f5b2853092a3648b1d22422b011641e893a56aafaf842d93e2ac75a"
+    sha256 cellar: :any,                 arm64_sonoma:  "4543c2694bb3bc240a45792de40e9ecef4229eeed3ff73f25dea245c0aaa7fa8"
+    sha256 cellar: :any,                 arm64_ventura: "dcbad1aeabc61e9e4ef5b0776cc40fcaab878e67931bf0b057847e3e9e69e86c"
+    sha256 cellar: :any,                 sonoma:        "eb839f56e6eb0d2d877a623eeab2ba46fa4a2f8e7c5b6133232caef634f14fb8"
+    sha256 cellar: :any,                 ventura:       "88b268f809736144bc316d83d38ece5c25c96c4b97b563173a8ca925fccddbc8"
+    sha256 cellar: :any_skip_relocation, x86_64_linux:  "af4677a7a0f6b40d288cb674a70c3c58fccaa970aff7b2ee0d68e5f387c6ce64"
+  end
+
+  depends_on "cmake" => :build
+
+  uses_from_macos "python" => :build
+
+  on_macos do
+    depends_on "llvm" if DevelopmentTools.clang_build_version <= 1500
+  end
+
+  fails_with :clang do
+    build 1500
+    cause "Requires C++20"
+  end
+
+  fails_with :gcc do
+    version "11"
+    cause "Requires C++20"
+  end
+
+  def install
+    ENV.llvm_clang if OS.mac? && DevelopmentTools.clang_build_version <= 1500
+
+    args = %W[
+      -DLIBUNICODE_EXAMPLES=OFF
+      -DLIBUNICODE_TESTING=OFF
+      -DLIBUNICODE_BENCHMARK=OFF
+      -DCMAKE_INSTALL_RPATH=#{rpath}
+    ]
+
+    system "cmake", "-S", ".", "-B", "build", *args, *std_cmake_args
+    system "cmake", "--build", "build"
+    system "cmake", "--install", "build"
+  end
+
+  test do
+    # ENV.llvm_clang doesn't work in the test block
+    ENV["CXX"] = Formula["llvm"].opt_bin/"clang++" if OS.mac? && DevelopmentTools.clang_build_version <= 1500
+
+    (testpath/"test.cpp").write <<~CPP
+      #include <iostream>
+      #include <libunicode/capi.h>
+
+      int main() {
+          u32_char_t u32_codepoints[] = { 'h', 'e', 'l', 'l', 'o', ' ', 0x1F30D };
+          int gc_count = u32_gc_count(u32_codepoints, 7);
+          std::cout << "Grapheme cluster count: " << gc_count << "\\n";
+
+          return 0;
+      }
+    CPP
+
+    system ENV.cxx, "-std=c++17", "-o", "test", "test.cpp", "-I#{include}", "-L#{lib}", "-lunicode"
+    assert_match "Grapheme cluster count: 7", shell_output("./test")
+
+    assert_match "HYPHEN", shell_output("#{bin}/unicode-query U+2D")
+  end
+end