use crane for the flake

flake.nix

@@ -1,99 +1,180 @@
 {
+  description = "A pixelflut stress testing tool";
+
   inputs = {
-    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+
+    crane.url = "github:ipetkov/crane";
+
     fenix = {
       url = "github:nix-community/fenix";
+      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.rust-analyzer-src.follows = "";
     };
     tsunami = {
       url = "github:itepastra/tsunami";
     };
+
+    flake-utils.url = "github:numtide/flake-utils";
+
+    advisory-db = {
+      url = "github:rustsec/advisory-db";
+      flake = false;
+    };
   };
 
   outputs =
     {
       self,
-      fenix,
       nixpkgs,
+      crane,
+      fenix,
+      flake-utils,
       tsunami,
+      advisory-db,
       ...
     }:
-    let
-      allSystems = [
-        "x86_64-linux" # 64-bit Intel/AMD Linux
-        "aarch64-linux" # 64-bit ARM Linux
-        "x86_64-darwin" # 64-bit Intel macOS
-        "aarch64-darwin" # 64-bit ARM macOS
-      ];
-      forAllSystems =
-        f:
-        nixpkgs.lib.genAttrs allSystems (
-          system:
-          f {
-            inherit system;
-            inherit tsunami;
-            pkgs = import nixpkgs { inherit system; };
-            fpkgs = import fenix { inherit system; };
+    flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        tsu = tsunami.packages.${system};
+
+        inherit (pkgs) lib;
+
+        craneLib = (crane.mkLib pkgs).overrideToolchain (p: fenix.packages.${system}.complete.toolchain);
+        src = craneLib.cleanCargoSource ./.;
+
+        # Common arguments can be set here to avoid repeating them later
+        commonArgs = {
+          inherit src;
+          strictDeps = true;
+
+          buildInputs =
+            [
+              # Add additional build inputs here
+            ]
+            ++ lib.optionals pkgs.stdenv.isDarwin [
+              # Additional darwin specific inputs can be set here
+              pkgs.libiconv
+            ];
+
+          # Additional environment variables can be set directly
+          # MY_CUSTOM_VAR = "some value";
+        };
+
+        craneLibLLvmTools = craneLib.overrideToolchain (
+          fenix.packages.${system}.complete.withComponents [
+            "cargo"
+            "llvm-tools"
+            "rustc"
+          ]
+        );
+
+        # Build *just* the cargo dependencies, so we can reuse
+        # all of that work (e.g. via cachix) when running in CI
+        cargoArtifacts = craneLib.buildDepsOnly commonArgs;
+
+        # Build the actual crate itself, reusing the dependency
+        # artifacts from above.
+        flurry = craneLib.buildPackage (
+          commonArgs
+          // {
+            inherit cargoArtifacts;
           }
         );
-    in
-    {
-      packages = forAllSystems (
-        { pkgs, fpkgs, ... }:
-        let
-          toolchain = fpkgs.minimal.toolchain;
-          fs = pkgs.lib.fileset;
-        in
-        rec {
-          default = flurry;
-          flurry =
-            (pkgs.makeRustPlatform {
-              cargo = toolchain;
-              rustc = toolchain;
-            }).buildRustPackage
-              {
-                pname = "flurry";
-                version = "0.1.0";
-                cargoLock.lockFile = ./Cargo.lock;
-                src = fs.toSource {
-                  root = ./.;
-                  fileset = fs.unions [
-                    ./Cargo.lock
-                    ./Cargo.toml
-                    ./src
-                    ./assets
-                  ];
-                };
-              };
-        }
-      );
-      devShells = forAllSystems (
-        {
-          pkgs,
-          fpkgs,
-          system,
-          ...
-        }:
-        let
-          ffpkgs = fpkgs.complete;
-        in
-        {
-          default = pkgs.mkShell {
-            buildInputs = [
-              ffpkgs.cargo
-              ffpkgs.clippy
-              ffpkgs.rust-src
-              ffpkgs.rustc
-              ffpkgs.rustfmt
-              pkgs.gcc
-              pkgs.wgo
-              tsunami.packages.${system}.tsunami
-            ];
+      in
+      {
+        checks = {
+          # Build the crate as part of `nix flake check` for convenience
+          inherit flurry;
+
+          # Run clippy (and deny all warnings) on the crate source,
+          # again, reusing the dependency artifacts from above.
+          #
+          # Note that this is done as a separate derivation so that
+          # we can block the CI if there are issues here, but not
+          # prevent downstream consumers from building our crate by itself.
+          flurry-clippy = craneLib.cargoClippy (
+            commonArgs
+            // {
+              inherit cargoArtifacts;
+              cargoClippyExtraArgs = "--all-targets -- --deny warnings";
+            }
+          );
+
+          flurry-doc = craneLib.cargoDoc (
+            commonArgs
+            // {
+              inherit cargoArtifacts;
+            }
+          );
+
+          # Check formatting
+          flurry-fmt = craneLib.cargoFmt {
+            inherit src;
           };
-        }
-      );
-      hydraJobs = {
-        devShell.x86_64-linux = self.devShells.x86_64-linux.default;
-        flurry.x86_64-linux = self.packages.x86_64-linux.flurry;
-      };
-    };
+
+          flurry-toml-fmt = craneLib.taploFmt {
+            src = pkgs.lib.sources.sourceFilesBySuffices src [ ".toml" ];
+            # taplo arguments can be further customized below as needed
+            # taploExtraArgs = "--config ./taplo.toml";
+          };
+
+          # Audit dependencies
+          flurry-audit = craneLib.cargoAudit {
+            inherit src advisory-db;
+          };
+
+          # Audit licenses
+          flurry-deny = craneLib.cargoDeny {
+            inherit src;
+          };
+
+          # Run tests with cargo-nextest
+          # Consider setting `doCheck = false` on `flurry` if you do not want
+          # the tests to run twice
+          flurry-nextest = craneLib.cargoNextest (
+            commonArgs
+            // {
+              inherit cargoArtifacts;
+              partitions = 1;
+              partitionType = "count";
+            }
+          );
+        };
+
+        packages =
+          {
+            default = flurry;
+          }
+          // lib.optionalAttrs (!pkgs.stdenv.isDarwin) {
+            flurry-llvm-coverage = craneLibLLvmTools.cargoLlvmCov (
+              commonArgs
+              // {
+                inherit cargoArtifacts;
+              }
+            );
+          };
+
+        apps.default = flake-utils.lib.mkApp {
+          drv = flurry;
+        };
+
+        devShells.default = craneLib.devShell {
+          # Inherit inputs from checks.
+          checks = self.checks.${system};
+
+          # Additional dev-shell environment variables can be set directly
+          # MY_CUSTOM_DEVELOPMENT_VAR = "something else";
+
+          # Extra inputs can be added here; cargo and rustc are provided by default.
+          packages = [
+            pkgs.wgo
+            pkgs.cargo-flamegraph
+            tsu.default
+          ];
+        };
+      }
+    );
 }