Explicitly patch shebangs

bin/mdpage.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 set -e
 

bin/page.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 expand() {
     TITLE="$1"

bin/rss.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 remove_nbsp() {
     sed 's#\ # #g'

bin/toc.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 
 set -e
 

knazarov.com.nix

@@ -9,6 +9,11 @@ stdenv.mkDerivation rec {
   dontPatch = true;
 
   installFlags = "PREFIX=${placeholder "out"} VERSION=${version}";
+
+  preBuild = ''
+    patchShebangs bin/*.sh
+  '';
+
   buildInputs = with pkgs; [
     gawk
     gnused