diff --git a/Aliases/postgresql@12 b/Aliases/postgresql@12
deleted file mode 120000
index 0e4f62d3434..00000000000
--- a/Aliases/postgresql@12
+++ /dev/null
@@ -1 +0,0 @@
-../Formula/postgresql.rb
\ No newline at end of file
diff --git a/Formula/postgresql@12.rb b/Formula/postgresql@12.rb
new file mode 100644
index 00000000000..3018f3176cc
--- /dev/null
+++ b/Formula/postgresql@12.rb
@@ -0,0 +1,128 @@
+class PostgresqlAT12 < Formula
+  desc "Object-relational database system"
+  homepage "https://www.postgresql.org/"
+  url "https://ftp.postgresql.org/pub/source/v12.4/postgresql-12.4.tar.bz2"
+  sha256 "bee93fbe2c32f59419cb162bcc0145c58da9a8644ee154a30b9a5ce47de606cc"
+  license "PostgreSQL"
+
+  keg_only :versioned_formula
+
+  depends_on "pkg-config" => :build
+  depends_on "icu4c"
+
+  # GSSAPI provided by Kerberos.framework crashes when forked.
+  # See https://github.com/Homebrew/homebrew-core/issues/47494.
+  depends_on "krb5"
+
+  depends_on "openssl@1.1"
+  depends_on "readline"
+
+  uses_from_macos "libxml2"
+  uses_from_macos "libxslt"
+  uses_from_macos "perl"
+
+  on_linux do
+    depends_on "util-linux"
+  end
+
+  def install
+    ENV.prepend "LDFLAGS", "-L#{Formula["openssl@1.1"].opt_lib} -L#{Formula["readline"].opt_lib}"
+    ENV.prepend "CPPFLAGS", "-I#{Formula["openssl@1.1"].opt_include} -I#{Formula["readline"].opt_include}"
+
+    args = %W[
+      --disable-debug
+      --prefix=#{prefix}
+      --datadir=#{opt_pkgshare}
+      --libdir=#{opt_lib}
+      --includedir=#{opt_include}
+      --sysconfdir=#{etc}
+      --docdir=#{doc}
+      --enable-thread-safety
+      --with-bonjour
+      --with-gssapi
+      --with-icu
+      --with-ldap
+      --with-libxml
+      --with-libxslt
+      --with-openssl
+      --with-pam
+      --with-perl
+      --with-tcl
+      --with-uuid=e2fs
+    ]
+
+    # PostgreSQL by default uses xcodebuild internally to determine this,
+    # which does not work on CLT-only installs.
+    args << "PG_SYSROOT=#{MacOS.sdk_path}" if MacOS.sdk_root_needed?
+
+    system "./configure", *args
+    system "make"
+    system "make", "install-world", "datadir=#{pkgshare}",
+                                    "libdir=#{lib}",
+                                    "pkglibdir=#{lib}/postgresql",
+                                    "includedir=#{include}",
+                                    "pkgincludedir=#{include}/postgresql",
+                                    "includedir_server=#{include}/postgresql/server",
+                                    "includedir_internal=#{include}/postgresql/internal"
+  end
+
+  def post_install
+    return if ENV["CI"]
+
+    (var/"log").mkpath
+    (var/"postgres").mkpath
+    unless File.exist? "#{var}/postgres/PG_VERSION"
+      system "#{bin}/initdb", "--locale=C", "-E", "UTF-8", "#{var}/postgres"
+    end
+  end
+
+  def caveats
+    <<~EOS
+      To migrate existing data from a previous major version of PostgreSQL run:
+        brew postgresql-upgrade-database
+
+      This formula has created a default database cluster with:
+        initdb --locale=C -E UTF-8 #{var}/postgres
+      For more details, read:
+        https://www.postgresql.org/docs/#{version.major}/app-initdb.html
+    EOS
+  end
+
+  plist_options manual: "pg_ctl -D #{HOMEBREW_PREFIX}/var/postgres@12 start"
+
+  def plist
+    <<~EOS
+      <?xml version="1.0" encoding="UTF-8"?>
+      <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+      <plist version="1.0">
+      <dict>
+        <key>KeepAlive</key>
+        <true/>
+        <key>Label</key>
+        <string>#{plist_name}</string>
+        <key>ProgramArguments</key>
+        <array>
+          <string>#{opt_bin}/postgres</string>
+          <string>-D</string>
+          <string>#{var}/postgres</string>
+        </array>
+        <key>RunAtLoad</key>
+        <true/>
+        <key>WorkingDirectory</key>
+        <string>#{HOMEBREW_PREFIX}</string>
+        <key>StandardOutPath</key>
+        <string>#{var}/log/postgres.log</string>
+        <key>StandardErrorPath</key>
+        <string>#{var}/log/postgres.log</string>
+      </dict>
+      </plist>
+    EOS
+  end
+
+  test do
+    system "#{bin}/initdb", testpath/"test" unless ENV["CI"]
+    assert_equal opt_pkgshare.to_s, shell_output("#{bin}/pg_config --sharedir").chomp
+    assert_equal opt_lib.to_s, shell_output("#{bin}/pg_config --libdir").chomp
+    assert_equal opt_lib.to_s, shell_output("#{bin}/pg_config --pkglibdir").chomp
+  end
+end