diff --git a/Formula/g/gnupg@2.5.rb b/Formula/g/gnupg@2.5.rb
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+++ b/Formula/g/gnupg@2.5.rb
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+class GnupgAT25 < Formula
+  desc "GNU Privacy Guard (OpenPGP) - production-ready pre 2.6-stable release"
+  homepage "https://lists.gnupg.org/pipermail/gnupg-announce/2025q4/000499.html"
+  url "https://gnupg.org/ftp/gcrypt/gnupg/gnupg-2.5.14.tar.bz2"
+  version "2.5.14-devel"
+  sha256 "25a622e625a1cc9078b5e3f7adf2bd02b86759170e2fbb8542bca8e907214610"
+  license "GPL-3.0-or-later"
+
+  keg_only :versioned_formula
+
+  depends_on "pkgconf" => :build      # enables: Keyboxd, TOFU support
+  depends_on "gnutls"                 # enables: Dirmngr, LDAP support, TLS support, Tor support (complete)
+  depends_on "libassuan"              # required
+  depends_on "libgcrypt"              # required
+  depends_on "libgpg-error"           # required
+  depends_on "libksba"                # required
+  depends_on "libusb"                 # enables: Smartcard (complete)
+  depends_on "npth"                   # required
+  depends_on "pinentry"               # ensures key passphrase entry
+  depends_on "readline"               # enables: Readline support
+
+  def install
+    mkdir "build" do
+      system "../configure",
+        "--disable-silent-rules",
+        "--enable-all-tests",
+        "--sysconfdir=#{etc}",
+        "--with-pinentry-pgm=#{Formula["pinentry"].opt_bin}/pinentry",
+        "--with-readline=#{Formula["readline"].opt_prefix}",
+        *std_configure_args
+
+      system "make"
+      # system "make", "check"        # inactive to satisfy "$ brew audit --strict"
+      system "make", "install"
+    end
+  end
+
+  def post_install
+    (var/"run").mkpath
+
+    # restart daemons after upgrades
+    quiet_system "gpgconf", "--kill", "all"
+  end
+
+  test do
+    (testpath/"batch.gpg").write <<-GPG
+      Key-Type: EDDSA
+      Key-Curve: ed25519
+      Key-Usage: cert,sign
+      Subkey-Type: ECDH
+      Subkey-Curve: cv25519
+      Subkey-Usage: encrypt
+      Name-Real: test
+      Name-Email: test@test
+      Expire-Date: 1d
+      %no-protection
+      %commit
+    GPG
+
+    begin
+      # pinentry is executable, which provides key passphrase entry:
+      #   gpg --quick-generate-key --batch --pinentry ask pinentry@test
+      system "test", "-x", "#{Formula["pinentry"].opt_bin}/pinentry"
+
+      # readline lib exists
+      libreadline_ext = OS.mac? ? "dylib" : "so"
+      system "test", "-f", "#{Formula["readline"].opt_lib}/libreadline.#{libreadline_ext}"
+
+      # keys are created
+      system bin/"gpg", "--batch", "--gen-key", "batch.gpg"
+
+      # file is encrypted and signed
+      file = "test.txt"
+      (testpath/file).write "test content"
+      system bin/"gpg", "--encrypt", "--sign", "--recipient", "test@test", file
+
+      # file is decrypted
+      system bin/"gpg", "--decrypt", "#{file}.gpg"
+    ensure
+      system bin/"gpgconf", "--kill", "all"
+    end
+  end
+end