diff --git a/readme.md b/readme.md
index 3266e46..42adbac 100644
--- a/readme.md
+++ b/readme.md
@@ -20,9 +20,9 @@ Now you can run it.
 
 ## Writing tests
 Make a root directory for your tests. Inside it, put executable files that
-exit `0` on success and something else on fail. Non-executable files are
-ignored, so you can store fixtures right next to your tests. Run urchin from
-inside the tests directory.
+exit `0` on success and something else on fail. Non-executable files and hidden
+files (dotfiles) are ignored, so you can store fixtures right next to your
+tests. Run urchin from inside the tests directory.
 
 ## More about writing tests
 Tests are organized recursively in directories, where the names of the files
@@ -55,6 +55,6 @@ directory.
 actually only includes files whose names contain "test". The test passes if the
 file exits 0; otherwise, it fails.
 
-Aside from files named '`setup`' or '`teardown`', files and directories are run
-only if they start with '`test`'. Thus, fixtures and libraries can be included
+Files are only run if they are executable, and files beginning with `.` are
+ignored. Thus, fixtures and libraries can be included
 sloppily within the test directory tree.
diff --git a/urchin b/urchin
index a51a805..33bad6f 100755
--- a/urchin
+++ b/urchin
@@ -6,11 +6,11 @@ recurse() {
     then
     (
       cd "$potential_test"
-      [ -f setup ] && sh setup
-      for test in test*
+      [ -f setup ] && [ -x setup ] && ./setup
+      for test in *
         do recurse "${test}"
       done
-      [ -f teardown ] && sh teardown
+      [ -f teardown ] && [ -x teardown ] && ./teardown
     )
   elif [ -x "$potential_test" ]
     then
@@ -28,12 +28,8 @@ recurse() {
   fi
 }
 
-if [ -d tests ]
-  then
-  echo Running tests
-  recurse tests
-  echo
-  echo Done
-else
-  echo 'No tests directory' && exit 1
-fi
+then
+echo Running tests
+recurse tests
+echo
+echo Done