Use writeShellApplication for packaging

flake.nix

@@ -24,7 +24,7 @@
         {
           default = self.packages.${system}.nixos-remote;
           docs = pkgs.callPackage ./docs { };
-          nixos-remote = pkgs.callPackage ./nixos-remote.nix { };
+          nixos-remote = pkgs.callPackage ./src { };
         });
       checks.x86_64-linux =
         let
@@ -32,6 +32,7 @@
           inputs = {
             inherit pkgs;
             inherit (disko.nixosModules) disko;
+            nixos-remote = self.packages.x86_64-linux.nixos-remote;
             kexec-installer = "${nixos-images.packages.${pkgs.system}.kexec-installer-nixos-unstable}/nixos-kexec-installer-${pkgs.stdenv.hostPlatform.system}.tar.gz";
           };
         in

nixos-remote.nix

@@ -1,39 +0,0 @@
-{ stdenvNoCC
-, makeWrapper
-, lib
-, openssh
-, gitMinimal
-, nix
-, coreutils
-, shellcheck
-, rsync
-, curl
-}:
-let
-  runtimeDeps = [
-    openssh
-    gitMinimal # for git flakes
-    rsync
-    nix
-    coreutils
-    curl # when uploading tarballs
-  ];
-in
-stdenvNoCC.mkDerivation {
-  name = "nixos-remote";
-  src = ./.;
-  nativeBuildInputs = [
-    makeWrapper
-    shellcheck
-  ];
-  installPhase = ''
-    install -D -m755 nixos-remote $out/bin/nixos-remote
-    wrapProgram "$out/bin/nixos-remote" \
-        --prefix PATH : "${lib.makeBinPath runtimeDeps}"
-  '';
-
-  doCheck = true;
-  checkPhase = ''
-    shellcheck ./nixos-remote
-  '';
-}

src/default.nix

@@ -0,0 +1,20 @@
+{ writeShellApplication
+, openssh
+, gitMinimal
+, rsync
+, nix
+, coreutils
+, curl
+}:
+writeShellApplication {
+  name = "nixos-remote";
+  text = builtins.readFile ./nixos-remote.sh;
+  runtimeInputs = [
+    openssh
+    gitMinimal # for git flakes
+    rsync
+    nix
+    coreutils
+    curl # when uploading tarballs
+  ];
+}

src/nixos-remote.sh

@@ -1,6 +1,3 @@
-#!/usr/bin/env bash
-set -eufo pipefail
-
 showUsage() {
   cat <<USAGE
 Usage: nixos-remote [options] ssh-host

tests/from-nixos-with-sudo.nix

@@ -8,7 +8,7 @@
     start_all()
     installer.succeed("echo super-secret > /tmp/disk-1.key")
     output = installer.succeed("""
-      ${../nixos-remote} \
+      nixos-remote \
         --no-ssh-copy-id \
         --debug \
         --kexec /etc/nixos-remote/kexec-installer \

tests/from-nixos.nix

@@ -18,7 +18,7 @@
     installer.succeed("mkdir -p /tmp/extra-files/var/lib/secrets")
     installer.succeed("echo value > /tmp/extra-files/var/lib/secrets/key")
     installer.succeed("""
-      ${../nixos-remote} \
+      nixos-remote \
         --no-ssh-copy-id \
         --debug \
         --kexec /etc/nixos-remote/kexec-installer \

tests/modules/installer.nix

@@ -12,6 +12,8 @@ in
     ${pkgs.coreutils}/bin/install -D -m600 ${./ssh-keys/ssh} /root/.ssh/id_rsa
   '';
 
+  environment.systemPackages = [ inputs.nixos-remote ];
+
   environment.etc = {
     "nixos-remote/disko".source = system-to-install.config.system.build.disko;
     "nixos-remote/system-to-install".source = system-to-install.config.system.build.toplevel;