From 1cabbce9f36424c59911856d8b18cd339e6f0970 Mon Sep 17 00:00:00 2001
From: Doron Behar <doron.behar@gmail.com>
Date: Wed, 20 Oct 2021 17:41:10 +0300
Subject: [PATCH] Add pistol-static compilation

---
 flake.lock | 11 ++++++-----
 flake.nix  | 45 +++++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 49 insertions(+), 7 deletions(-)

diff --git a/flake.lock b/flake.lock
index ce279c4..2c13907 100644
--- a/flake.lock
+++ b/flake.lock
@@ -61,15 +61,16 @@
         ]
       },
       "locked": {
-        "lastModified": 1627572165,
-        "narHash": "sha256-MFpwnkvQpauj799b4QTBJQFEddbD02+Ln5k92QyHOSk=",
-        "owner": "tweag",
+        "lastModified": 1638001840,
+        "narHash": "sha256-Qknxy+YjVA39v/LwiUNsAcMAg9Df8aYAuqkH+EiAHRA=",
+        "owner": "doronbehar",
         "repo": "gomod2nix",
-        "rev": "67f22dd738d092c6ba88e420350ada0ed4992ae8",
+        "rev": "242884158539d4cc0bdc74ab718c499bad785a14",
         "type": "github"
       },
       "original": {
-        "owner": "tweag",
+        "owner": "doronbehar",
+        "ref": "go-stdenv",
         "repo": "gomod2nix",
         "type": "github"
       }
diff --git a/flake.nix b/flake.nix
index f830c14..096a11e 100644
--- a/flake.nix
+++ b/flake.nix
@@ -11,7 +11,8 @@
     flake = false;
   };
   inputs.gomod2nix = {
-    url = "github:tweag/gomod2nix";
+    # For static compilation I need: https://github.com/tweag/gomod2nix/pull/24
+    url = "github:doronbehar/gomod2nix/go-stdenv";
     inputs.nixpkgs.follows = "nixpkgs";
     inputs.utils.follows = "flake-utils";
   };
@@ -39,6 +40,9 @@
       # https://discourse.nixos.org/t/passing-git-commit-hash-and-tag-to-build-with-flakes/11355/2
       version_rev = if (self ? rev) then (builtins.substring 0 8 self.rev) else "dirty";
       version = "${pkgs.lib.fileContents ./VERSION}-${version_rev}-flake";
+      buildGoApplicationStatic = pkgs.buildGoApplication.override {
+        stdenv = pkgs.pkgsStatic.stdenv;
+      };
       pistol = pkgs.buildGoApplication {
         pname = "pistol";
         inherit version;
@@ -79,6 +83,38 @@
         ;
         CGO_ENABLED = 1;
       };
+      pistol-static = buildGoApplicationStatic {
+        inherit (pistol)
+          pname
+          version
+          src
+          subPackages
+          postBuild
+          CGO_ENABLED
+          modules
+          meta
+        ;
+        nativeBuildInputs = pistol.nativeBuildInputs ++ [
+          pkgs.removeReferencesTo
+        ];
+        buildInputs = [
+          pkgs.pkgsStatic.file
+          pkgs.pkgsStatic.zlib
+        ];
+        # From some reason even though zlib is static we need this, but it
+        # doesn't create a real reference to zlib.
+        NIX_LDFLAGS = "-lz";
+        postFixup = ''
+          # Remove unnecessary references to zlib.
+          rm -r $out/nix-support
+          # Remove more unnecessary references which I don't know the source of
+          # which. I guess they are due to features of some go modules I don't
+          # use.
+          remove-references-to -t ${pkgs.mailcap} $out/bin/pistol
+          remove-references-to -t ${pkgs.iana-etc} $out/bin/pistol
+          remove-references-to -t ${pkgs.tzdata} $out/bin/pistol
+        '';
+      };
     in rec {
       devShell = pkgs.mkShell {
         inherit (pistol) buildInputs;
@@ -88,7 +124,12 @@
           pkgs.gomod2nix
         ];
       };
-      packages.pistol = pistol;
+      packages = {
+        inherit
+          pistol
+          pistol-static
+        ;
+      };
       defaultPackage = pistol;
       apps.pistol = {
         type = "app";