diff --git a/pkgs/servers/sql/postgresql/pg_hll/default.nix b/pkgs/servers/sql/postgresql/pg_hll/default.nix
new file mode 100644
index 000000000000..6c453f6a40c3
--- /dev/null
+++ b/pkgs/servers/sql/postgresql/pg_hll/default.nix
@@ -0,0 +1,31 @@
+{ stdenv, fetchFromGitHub, postgresql }:
+
+stdenv.mkDerivation rec {
+  name = "pg_hll-${version}";
+  version = "2.10.2-${builtins.substring 0 7 src.rev}";
+
+  buildInputs = [ postgresql ];
+
+  src = fetchFromGitHub {
+    owner  = "citusdata";
+    repo   = "postgresql-hll";
+    rev    = "9af41684d479a3097bab87d04936702c9e6baf5c";
+    sha256 = "044x9v9kjhxb0idqb9f5i7c3yygxxsqliswl4kspqy9f9qcblckl";
+  };
+
+  installPhase = ''
+    mkdir -p $out/{lib,share/extension}
+
+    cp *.so      $out/lib
+    cp *.sql     $out/share/extension
+    cp *.control $out/share/extension
+  '';
+
+  meta = with stdenv.lib; {
+    description = "HyperLogLog for PostgreSQL";
+    homepage    = https://www.citusdata.com/;
+    maintainers = with maintainers; [ thoughtpolice ];
+    platforms   = platforms.linux;
+    license     = licenses.asl20;
+  };
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 37f4d6b36562..95f78c74fc2c 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2764,6 +2764,8 @@ with pkgs;
 
   cstore_fdw = callPackage ../servers/sql/postgresql/cstore_fdw {};
 
+  pg_hll = callPackage ../servers/sql/postgresql/pg_hll {};
+
   pg_cron = callPackage ../servers/sql/postgresql/pg_cron {};
 
   pgtap = callPackage ../servers/sql/postgresql/pgtap {};