Use protoc from nix when available

build.sbt

@@ -942,6 +942,10 @@ lazy val bootstrapped = projectMatrix
     Compile / PB.protoSources ++= Seq(
       exampleGeneratedResourcesOutput.value
     ),
+    Compile / PB.protocExecutable := sys.env
+      .get("PROTOC_PATH")
+      .map(file(_))
+      .getOrElse((Compile / PB.protocExecutable).value),
     Compile / PB.targets := Seq(
       scalapb.gen() -> (Compile / sourceManaged).value / "scalapb"
     ),

flake.nix

@@ -2,31 +2,31 @@
   inputs.nixpkgs.url = "github:nixos/nixpkgs";
   inputs.flake-utils.url = "github:numtide/flake-utils";
 
-  outputs = { self, nixpkgs, flake-utils, ... }@inputs:
+  outputs = { nixpkgs, flake-utils, ... }:
     flake-utils.lib.eachDefaultSystem (system:
       let
         pkgs = import nixpkgs { inherit system; };
-        shellPackages = [
-          "jre"
-          "sbt"
-          "nodejs-16_x"
-          "yarn"
+        shellPackages = with pkgs; [
+          temurin-jre-bin-17
+          nodejs-18_x
+          yarn
+          (pkgs.sbt.override { jre = pkgs.temurin-jre-bin-17; })
         ];
       in
       {
         devShells.default = pkgs.mkShell {
-          buildInputs = map (pkgName: pkgs.${pkgName}) shellPackages;
-          nativeBuildInputs = [ pkgs.openssl pkgs.zlib ];
+          buildInputs = shellPackages;
+          nativeBuildInputs = [ pkgs.openssl pkgs.zlib pkgs.protobuf3_21 ];
           welcomeMessage = ''
             Welcome to the smithy4s Nix shell! 👋
             Available packages:
-            ${builtins.concatStringsSep "\n" (map (n : "- ${n}") shellPackages)}
+            ${builtins.concatStringsSep "\n" (map (n : "- ${n.name}") shellPackages)}
           '';
 
           shellHook = ''
             echo "$welcomeMessage"
           '';
-          LD_LIBRARY_PATH = "${pkgs.stdenv.cc.cc.lib}/lib";
+          PROTOC_PATH = pkgs.lib.getExe pkgs.protobuf3_21;
         };
       }
     );