diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index d5e0038..ae76969 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -852,6 +852,7 @@
     expect: [['#!/path/expect']],
     gnuplot: [['#!/path/gnuplot']],
     make:   [['#!/path/make']],
+    nix:    [['#!/path/nix-shell']],
     pike:   [['#!/path/pike'],
             ['#!/path/pike0'],
             ['#!/path/pike9']],
@@ -902,6 +903,7 @@
     scheme: [['#!/usr/bin/env VAR=val --ignore-environment scheme']],
     python: [['#!/usr/bin/env VAR=val -S python -w -T']],
     wml: [['#!/usr/bin/env VAR=val --split-string wml']],
+    nix: [['#!/usr/bin/env nix-shell']],
   }
 enddef
 
diff --git a/src/version.c b/src/version.c
index 90331ed..bad9e54 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1620,
+/**/
     1619,
 /**/
     1618,