diff --git a/scripts/nix-build.in b/scripts/nix-build.in
index b7c923f88..12826323c 100755
--- a/scripts/nix-build.in
+++ b/scripts/nix-build.in
@@ -5,6 +5,8 @@ use strict;
 use Nix::Config;
 use Nix::Store;
 use Nix::Utils;
+use File::Basename;
+use Cwd;
 
 binmode STDERR, ":encoding(utf8)";
 
@@ -219,6 +221,11 @@ foreach my $expr (@exprs) {
     # Instantiate.
     my @drvPaths;
     if ($expr !~ /^\/.*\.drv$/) {
+        # If we're in a #! script, interpret filenames relative to the
+        # script.
+        $expr = dirname(Cwd::abs_path($script)) . "/" . $expr
+            if $inShebang && $expr !~ /^\//;
+
         # !!! would prefer the perl 5.8.0 pipe open feature here.
         my $pid = open(DRVPATHS, "-|") || exec "$Nix::Config::binDir/nix-instantiate", "--add-root", $drvLink, "--indirect", @instArgs, $expr;
         while (<DRVPATHS>) {chomp; push @drvPaths, $_;}