[TMP]: Add some benchmarking tools

Not intended to be merged (at least definitely not as it is)

benchmark.sh

@@ -0,0 +1,51 @@
+#!/bin/sh
+
+set -euo pipefail
+set -x
+
+callNix () {
+    nix \
+        --experimental-features "nix-command flakes" \
+        --store /tmp/nix \
+        "$@"
+}
+
+callBuild () {
+    callNix \
+        eval --impure --file "$THINGTOBENCH" drvPath \
+        "$@"
+}
+getCompletions () {
+    NIX_GET_COMPLETIONS=6 callNix build "github:NixOS/nixpkgs?rev=ad0d20345219790533ebe06571f82ed6b034db31#firef" "$@"
+}
+runSearch () {
+    callNix search "github:NixOS/nixpkgs?rev=ad0d20345219790533ebe06571f82ed6b034db31" firefox "$@"
+}
+
+noCache () {
+    "$@" --option eval-cache false
+}
+coldCache () {
+    if [[ -e ~/.cache/nix/eval-cache-v2 || -e ~/.cache/nix/eval-cache-v3 ]]; then
+        echo "Error: The cache should be clean"
+        exit 1
+    fi
+    "$@"
+}
+
+run_all () {
+
+    mkdir -p "$out"
+
+    NIX_SHOW_STATS=1 NIX_SHOW_STATS_PATH=$out/eval-stats.json bash $0 noCache callBuild
+
+    hyperfine \
+        --warmup 2 \
+        --export-csv "$out/result.csv" \
+        --export-json "$out/result.json" \
+        --export-markdown "$out/result.md" \
+        --style basic \
+        --prepare '' "bash $0 noCache callBuild"
+}
+
+"$@"

flake.nix

@@ -294,6 +294,13 @@
             '';
         };
 
+        nix-benchmarks = prev.runCommandNoCC "nix-benchmarks" {
+          buildInputs = [ final.nix prev.hyperfine ];
+          THINGTOBENCH = ./thingToBench.nix;
+          NIX_PATH="nixpkgs=${prev.path}";
+        } ''
+          bash ${./benchmark.sh} run_all
+        '';
       };
 
       hydraJobs = {
@@ -485,7 +492,7 @@
       });
 
       packages = forAllSystems (system: {
-        inherit (nixpkgsFor.${system}) nix;
+        inherit (nixpkgsFor.${system}) nix nix-benchmarks;
       } // nixpkgs.lib.optionalAttrs (builtins.elem system linux64BitSystems) {
         nix-static = let
           nixpkgs = nixpkgsFor.${system}.pkgsStatic;

thingToBench.nix

@@ -0,0 +1,12 @@
+let
+  # pkgs = (builtins.getFlake "github:NixOS/nixpkgs?rev=ad0d20345219790533ebe06571f82ed6b034db31").legacyPackages.x86_64-linux;
+  pkgs = import <nixpkgs> {};
+in
+  pkgs.runCommandNoCC "foo" {
+    buildInputs = [
+      pkgs.firefox
+      pkgs.pandoc
+      # pkgs.nixosTests.xfce
+    ];
+  }
+  "echo bar > $out"