diff --git a/.github/workflows/nix.yml b/.github/workflows/nix.yml
index 91177d788..80696d2f1 100644
--- a/.github/workflows/nix.yml
+++ b/.github/workflows/nix.yml
@@ -45,4 +45,4 @@ jobs:
       - uses: cachix/install-nix-action@v15
         with:
           nix_path: nixpkgs=channel:nixos-unstable
-      - run: nix build
+      - run: nix build .?submodules=1
diff --git a/default.nix b/default.nix
index 3901d56c0..2bf35251c 100644
--- a/default.nix
+++ b/default.nix
@@ -1,24 +1,14 @@
 { pkgs ? import <nixpkgs> { }
 , lib ? pkgs.lib
 , stdenv ? pkgs.stdenv
-, fetchgit
 }:
-let
-  sexpSource = fetchgit {
-    name = "sexp";
-    url = "https://github.com/rnpgp/sexp.git";
-    rev = "refs/tags/v0.7.0";
-    sha256 = "MA54sKyHBFB6ZAGQCHFswIeiVn/TgTjGhP1dE+fS+sU=";
-  };
-in
+
 stdenv.mkDerivation rec {
   pname = "rnp";
   version = "unstable";
 
   src = ./.;
 
-  sexp = import sexpSource { inherit pkgs; };
-
   buildInputs = with pkgs; [ zlib bzip2 json_c botan2 ];
 
   cmakeFlags = [
@@ -41,7 +31,6 @@ stdenv.mkDerivation rec {
     commitEpoch=$(date +%s)
     baseVersion=$(cat version.txt)
     echo "v$baseVersion-0-g0-dirty+$commitEpoch" > version.txt
-
     # For generating the correct timestamp in cmake
     export SOURCE_DATE_EPOCH=$commitEpoch
   '';
@@ -53,4 +42,4 @@ stdenv.mkDerivation rec {
     platforms = platforms.all;
     maintainers = with maintainers; [ ribose-jeffreylau ];
   };
-}
+}
\ No newline at end of file
diff --git a/flake.lock b/flake.lock
index bbd61f3ef..5a119b9fc 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,26 +2,11 @@
   "nodes": {
     "flake-utils": {
       "locked": {
-        "lastModified": 1667395993,
-        "narHash": "sha256-nuEHfE/LcWyuSWnS8t12N1wc105Qtau+/OdUAjtQ0rA=",
+        "lastModified": 1678901627,
+        "narHash": "sha256-U02riOqrKKzwjsxc/400XnElV+UtPUQWpANPlyazjH0=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "5aed5285a952e0b949eb3ba02c12fa4fcfef535f",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
-    "flake-utils_2": {
-      "locked": {
-        "lastModified": 1667395993,
-        "narHash": "sha256-nuEHfE/LcWyuSWnS8t12N1wc105Qtau+/OdUAjtQ0rA=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "5aed5285a952e0b949eb3ba02c12fa4fcfef535f",
+        "rev": "93a2b84fc4b70d9e089d029deacc3583435c2ed6",
         "type": "github"
       },
       "original": {
@@ -32,26 +17,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1669624546,
-        "narHash": "sha256-lfGjMcCJ9wgiqiNDC7bExbFNqemX7HYJi2J1Rx50HaE=",
-        "owner": "nixos",
-        "repo": "nixpkgs",
-        "rev": "78dd6da1b938d662bc27159efa5a93185ff2165b",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nixos",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "nixpkgs_2": {
-      "locked": {
-        "lastModified": 1669023499,
-        "narHash": "sha256-iXvCW2VaH4LJD1AElk82/FaR7yepj/BqLYOJ3GAhdKQ=",
+        "lastModified": 1679685564,
+        "narHash": "sha256-PgzKcXZWCf9MjU4F+9WCQyQER5Mf1qbi2dh65QTD5Vc=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "c107fb66da7c150110fe301c38932eeccf5f9824",
+        "rev": "0dbcdf71be50604de48a67e6cf1d0a9a5911f145",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index dbb6eb194..c9ddc201c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -6,7 +6,7 @@
     flake-utils.url = "github:numtide/flake-utils";
   };
 
-  outputs = { self, nixpkgs, flake-utils, sexp }:
+  outputs = { self, nixpkgs, flake-utils }:
     flake-utils.lib.eachDefaultSystem (system:
       let
         pkgs = nixpkgs.legacyPackages.${system};
@@ -23,4 +23,4 @@
           ];
         };
       });
-}
+}
\ No newline at end of file