diff --git a/t/data/nkjp.zip b/t/data/nkjp.zip
new file mode 100644
index 0000000..2ac910c
--- /dev/null
+++ b/t/data/nkjp.zip
Binary files differ
diff --git a/t/test.t b/t/test.t
index 7954e6d..ac3550c 100644
--- a/t/test.t
+++ b/t/test.t
@@ -1,6 +1,6 @@
 use strict;
 use warnings;
-use Test::More tests => 50;
+use Test::More tests => 53;
 use Test::Script;
 use Test::TempDir::Tiny;
 use File::Copy;
@@ -200,4 +200,7 @@
 script_stderr_like "WARNING: No valid input document.*token offsets missing", "Warn on missing token offsets";
 script_stderr_like qr@WARNING: No valid input document.*text.id .*missing@,   "Warn on missing text ids";
 
+script_runs([ 'script/korapxml2conllu', "t/data/nkjp.zip" ], "Runs korapxml2conllu on nkjp test data");
+script_stderr_unlike("Use of uninitialized value", "Handles lonely docid parameters (line separated from layer elements)");
+script_stdout_like("\n9\twesołości\twesołość\tsubst\tsubst\tsg:gen:f", "Correctly converts nkjp annotations");
 done_testing;