diff --git a/pkgs/development/libraries/ada/gnatprove/default.nix b/pkgs/development/libraries/ada/gnatprove/default.nix
index ce0f3cc432c1..4e7c4d964af6 100644
--- a/pkgs/development/libraries/ada/gnatprove/default.nix
+++ b/pkgs/development/libraries/ada/gnatprove/default.nix
@@ -1,29 +1,52 @@
 { stdenv
 , lib
 , fetchFromGitHub
-, gnat12
+, gnat
 , gnatcoll-core
 , gprbuild
 , python3
 , ocamlPackages
 , makeWrapper
 }:
+let
+  gnat_version = lib.versions.major gnat.version;
 
-stdenv.mkDerivation rec {
-  pname = "gnatprove";
-  version = "unstable-2022-05-25";
-
-  src = fetchFromGitHub {
+  fetchSpark2014 = { rev, sha256 } : fetchFromGitHub {
     owner = "AdaCore";
     repo = "spark2014";
-    # commit on fsf-12 branch
-    rev = "ab34e07080a769b63beacc141707b5885c49d375";
-    sha256 = "sha256-7pe3eWitpxmqzjW6qEIEuN0qr2IR+kJ7Ssc9pTBcCD8=";
     fetchSubmodules = true;
+    inherit rev sha256;
   };
 
+  spark2014 = {
+    "12" = {
+      src = fetchSpark2014 {
+        rev = "ab34e07080a769b63beacc141707b5885c49d375"; # branch fsf-12
+        sha256 = "sha256-7pe3eWitpxmqzjW6qEIEuN0qr2IR+kJ7Ssc9pTBcCD8=";
+      };
+      commit_date = "2022-05-25";
+    };
+    "13" = {
+      src = fetchSpark2014 {
+        rev = "12db22e854defa9d1c993ef904af1e72330a68ca"; # branch fsf-13
+        sha256 = "sha256-mZWP9yF1O4knCiXx8CqolnS+93bM+hTQy40cd0HZmwI=";
+      };
+      commit_date = "2023-01-05";
+    };
+  };
+
+  thisSpark = spark2014.${gnat_version} or
+    (builtins.throw "GNATprove depend on a specific GNAT version and can't be built using GNAT ${gnat_version}.");
+
+in
+stdenv.mkDerivation rec {
+  pname = "gnatprove";
+  version = "fsf-${gnat_version}_${thisSpark.commit_date}";
+
+  src = thisSpark.src;
+
   nativeBuildInputs = [
-    gnat12
+    gnat
     gprbuild
     python3
     ocamlPackages.ocaml
@@ -43,8 +66,8 @@ stdenv.mkDerivation rec {
 
   postPatch = ''
     # gnat2why/gnat_src points to the GNAT sources
-    tar xf ${gnat12.cc.src} gcc-${gnat12.cc.version}/gcc/ada
-    mv gcc-${gnat12.cc.version}/gcc/ada gnat2why/gnat_src
+    tar xf ${gnat.cc.src} gcc-${gnat.cc.version}/gcc/ada
+    mv gcc-${gnat.cc.version}/gcc/ada gnat2why/gnat_src
   '';
 
   configurePhase = ''