diff --git a/.envrc.sample b/.envrc
similarity index 100%
rename from .envrc.sample
rename to .envrc
diff --git a/flake.lock b/flake.lock
index 4bf02e17..25f12644 100644
--- a/flake.lock
+++ b/flake.lock
@@ -18,11 +18,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1701253981,
-        "narHash": "sha256-ztaDIyZ7HrTAfEEUt9AtTDNoCYxUdSd6NrRHaYOIxtk=",
+        "lastModified": 1704538339,
+        "narHash": "sha256-1734d3mQuux9ySvwf6axRWZRBhtcZA9Q8eftD6EZg6U=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "e92039b55bcd58469325ded85d4f58dd5a4eaf58",
+        "rev": "46ae0210ce163b3cba6c7da08840c1d63de9c701",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index cc830c7e..ebaeb81f 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,5 +1,5 @@
 {
-  description = "Highly customizable Wayland bar for Sway and Wlroots based compositors.";
+  description = "Highly customizable Wayland bar for Sway and Wlroots based compositors";
 
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
@@ -15,7 +15,8 @@
       genSystems = func: lib.genAttrs [
         "x86_64-linux"
         "aarch64-linux"
-      ] (system: func (import nixpkgs { inherit system; }));
+      ]
+        (system: func (import nixpkgs { inherit system; }));
 
       mkDate = longDate: (lib.concatStringsSep "-" [
         (builtins.substring 0 4 longDate)
@@ -24,6 +25,27 @@
       ]);
     in
     {
+      devShells = genSystems
+        (pkgs:
+          {
+            default =
+              pkgs.mkShell
+                {
+                  name = "waybar-shell";
+
+                  # inherit attributes from upstream nixpkgs derivation
+                  inherit (pkgs.waybar) buildInputs depsBuildBuild depsBuildBuildPropagated depsBuildTarget
+                    depsBuildTargetPropagated depsHostHost depsHostHostPropagated depsTargetTarget
+                    depsTargetTargetPropagated propagatedBuildInputs propagatedNativeBuildInputs strictDeps;
+
+                  # overrides for local development
+                  nativeBuildInputs = pkgs.waybar.nativeBuildInputs ++ (with pkgs; [
+                    clang-tools
+                    gdb
+                  ]);
+                };
+          });
+
       overlays.default = final: prev: {
         waybar = final.callPackage ./nix/default.nix {
           # take the first "version: '...'" from meson.build
@@ -35,27 +57,11 @@
             + "+date=" + (mkDate (self.lastModifiedDate or "19700101")) + "_" + (self.shortRev or "dirty");
         };
       };
+
       packages = genSystems (pkgs:
         let packages = self.overlays.default pkgs pkgs;
         in packages // {
           default = packages.waybar;
         });
-    } //
-    genSystems (pkgs: {
-      devShells.default =
-        pkgs.mkShell {
-          name = "waybar-shell";
-
-          # most of these aren't actually used in the waybar derivation, this is just in case
-          # they will ever start being used
-          inherit (pkgs.waybar) buildInputs depsBuildBuild depsBuildBuildPropagated depsBuildTarget
-            depsBuildTargetPropagated depsHostHost depsHostHostPropagated depsTargetTarget
-            depsTargetTargetPropagated propagatedBuildInputs propagatedNativeBuildInputs strictDeps;
-
-          nativeBuildInputs = pkgs.waybar.nativeBuildInputs ++ (with pkgs; [
-            clang-tools
-            gdb
-          ]);
-        };
-    });
+    };
 }
diff --git a/nix/default.nix b/nix/default.nix
index 5efa5da4..e2643084 100644
--- a/nix/default.nix
+++ b/nix/default.nix
@@ -1,9 +1,20 @@
 { lib
+, pkgs
 , waybar
 , version
 }:
-
-waybar.overrideAttrs (prev: {
+let
+  catch2_3 = {
+    src = pkgs.fetchFromGitHub
+      {
+        owner = "catchorg";
+        repo = "Catch2";
+        rev = "v3.5.1";
+        hash = "sha256-OyYNUfnu6h1+MfCF8O+awQ4Usad0qrdCtdZhYgOY+Vw=";
+      };
+  };
+in
+(waybar.overrideAttrs (oldAttrs: rec {
   inherit version;
 
   src = lib.cleanSourceWith {
@@ -11,3 +22,9 @@ waybar.overrideAttrs (prev: {
     src = lib.cleanSource ../.;
   };
 })
+).override {
+  catch2_3 = pkgs.catch2_3.overrideAttrs (oldAttrs: {
+    version = "3.5.1";
+    src = catch2_3.src;
+  });
+}