From 6b8c09bffca82c1373c38586cac2032088f0e5bf Mon Sep 17 00:00:00 2001
From: Jim Fowler <fowler@math.osu.edu>
Date: Mon, 7 Jan 2019 21:06:09 -0500
Subject: [PATCH] more idiomatic nix

---
 pkgs/tools/security/hashcash/default.nix | 26 ++++++++++++++----------
 1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/pkgs/tools/security/hashcash/default.nix b/pkgs/tools/security/hashcash/default.nix
index 337837f3116d..a28822ecd951 100644
--- a/pkgs/tools/security/hashcash/default.nix
+++ b/pkgs/tools/security/hashcash/default.nix
@@ -1,23 +1,27 @@
 { stdenv, fetchurl, openssl }:
 
 stdenv.mkDerivation rec {
-  name = "hashcash-${version}";
+  pname = "hashcash";
   version = "1.22";
-
+  
   buildInputs = [ openssl ];
 
   src = fetchurl {
-      url = "http://www.hashcash.org/source/hashcash-1.22.tgz";
-      sha256 = "15kqaimwb2y8wvzpn73021bvay9mz1gqqfc40gk4hj6f84nz34h1";
+    url = "http://www.hashcash.org/source/hashcash-${version}.tgz";
+    sha256 = "15kqaimwb2y8wvzpn73021bvay9mz1gqqfc40gk4hj6f84nz34h1";
   };
+  
+  makeFlags = [
+    "generic-openssl"
+    "LIBCRYPTO=-lcrypto"
+  ];
 
-  makeFlags = "generic-openssl LIBCRYPTO=-lcrypto";
-
-  installPhase = ''
-    install -D -m 0755 --target $out/bin hashcash sha1
-    install -D -m 0444 hashcash.1 $out/share/man/man1/hashcash.1
-  '';
-
+  installFlags = [
+    "INSTALL_PATH=${placeholder "out"}/bin"
+    "MAN_INSTALL_PATH=${placeholder "out"}/share/man/man1"
+    "DOC_INSTALL_PATH=${placeholder "out"}/share/doc/hashcash-$(version)"
+  ];
+  
   meta = with stdenv.lib; {
     description = "Proof-of-work algorithm used as spam and denial-of-service counter measure";
     homepage = http://hashcash.org;