diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..3550a30
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use flake
diff --git a/flake.lock b/flake.lock
index 0c4da0f..dade030 100644
--- a/flake.lock
+++ b/flake.lock
@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1755615617,
-        "narHash": "sha256-HMwfAJBdrr8wXAkbGhtcby1zGFvs+StOp19xNsbqdOg=",
+        "lastModified": 1756542300,
+        "narHash": "sha256-tlOn88coG5fzdyqz6R93SQL5Gpq+m/DsWpekNFhqPQk=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "20075955deac2583bb12f07151c2df830ef346b4",
+        "rev": "d7600c775f877cd87b4f5a831c28aa94137377aa",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index 3d2ffbf..56eeb1f 100644
--- a/flake.nix
+++ b/flake.nix
@@ -16,6 +16,8 @@
         buildInputs = with pkgs; [
           typst
           typstyle
+          python313Packages.sympy
+          python313Packages.matplotlib
         ];
         shellHook = ''
           echo welcome!