diff --git a/README.md b/README.md
index d49c95a..5a6ea31 100644
--- a/README.md
+++ b/README.md
@@ -79,7 +79,7 @@ this by cloning the source repository to somewhere on your machine and running
 `pip install`:
 
 ```shell
-git clone https://github.com/olin/focstest.git
+git clone --branch=release https://github.com/olin/focstest.git  # clone a stable version
 pip install focstest/
 ```
 
@@ -119,15 +119,14 @@ refresh `focstest`'s copy, use the `--update-cache` flag:
 focstest homework2.ml --update-cache
 ```
 
-
 `focstest` uses a standard python-powered command-line interface. You can always
 ask it for help with `--help` or `-h`.
 
-```
+```shell
 $ focstest --help
-usage: focstest [-h] [-u URL] [-v] [--log-level {debug,info,warning}] [-uc]
-                   [-U [N [N ...]] | -S [N [N ...]]]
-                   ocaml-file
+usage: focstest [-h] [--version] [--url URL] [-v] [-uc] [-u [N [N ...]] | -s
+                [N [N ...]]]
+                ocaml-file
 
 Run ocaml "doctests".
 
@@ -136,15 +135,17 @@ positional arguments:
 
 optional arguments:
   -h, --help            show this help message and exit
-  -u URL, --url URL     a url to scrape tests from
+  --version             show program's version number and exit
+  --url URL             a url to scrape tests from (usually automagically
+                        guessed from ocaml-file)
   -v, --verbose         increase test output verbosity
-  --log-level {debug,info,warning}
-                        the program log level
   -uc, --update-cache   update cached files
-  -U [N [N ...]], --use-suites [N [N ...]]
+  -u [N [N ...]], --use-suites [N [N ...]]
                         test suites to use exclusively, indexed from 1
-  -S [N [N ...]], --skip-suites [N [N ...]]
+  -s [N [N ...]], --skip-suites [N [N ...]]
                         test suites to skip, indexed from 1
+
+Submit bugs to <https://github.com/olin/focstest/issues/>.
 ```
 
 For most homeworks, the workflow that I've used is going question by question
@@ -181,3 +182,10 @@ Run `pipenv install --dev` to install all of the dev packages.
 Run tests with `python -m unittest discover`.
 
 Want to use it while you hack on it? Install it with `pip install -e`.
+
+You can set `focstest`'s logging level with the `LOG_LEVEL` environment variable.
+The possible values are all of python's usual logging levels, set it to `DEBUG`
+for more output.
+```shell
+$ LOG_LEVEL=DEBUG focstest homework3.ml
+```
diff --git a/focstest.py b/focstest.py
index ec5e150..eaed45d 100755
--- a/focstest.py
+++ b/focstest.py
@@ -196,27 +196,32 @@ def main():
         epilog='Submit bugs to <https://github.com/olin/focstest/issues/>.')
     parser.add_argument('--version', action='version', version=__version__)
     input_types = parser.add_mutually_exclusive_group(required=False)
-    input_types.add_argument('-u', '--url', type=str,
-                             help='a url to scrape tests from (usually automagically guessed based on ocaml-file)')
-    # input_types.add_argument('-f', '--file', type=str,
-    #                          help='a file to load tests from')
+    input_types.add_argument('--url', type=str,
+                             help='a url to scrape tests from (usually automagically guessed from ocaml-file)')
     parser.add_argument('ocaml-file', type=str,
                         help='the ocaml file to test against')
     parser.add_argument('-v', '--verbose', action='store_true',
                         help='increase test output verbosity')
-    parser.add_argument('--log-level', choices=['debug', 'info', 'warning'],
-                        help='the program log level')
     parser.add_argument('-uc', '--update-cache', action='store_true',
                         help='update cached files')
     test_selection = parser.add_mutually_exclusive_group(required=False)
-    test_selection.add_argument('-U', '--use-suites', metavar='N', type=int, nargs='*',
+    test_selection.add_argument('-u', '--use-suites', metavar='N', type=int, nargs='*',
                                 help='test suites to use exclusively, indexed from 1')
-    test_selection.add_argument('-S', '--skip-suites', metavar='N', type=int, nargs='*',
+    test_selection.add_argument('-s', '--skip-suites', metavar='N', type=int, nargs='*',
                                 help='test suites to skip, indexed from 1')
     args = parser.parse_args()
-    if args.log_level:
-        numeric_level = getattr(logging, args.log_level.upper(), None)
-        logger.setLevel(numeric_level)
+
+    # check environment var for logging level
+    log_level = os.getenv('LOG_LEVEL')
+    if log_level is not None:
+        log_level = log_level.upper()
+        try:
+            numeric_level = getattr(logging, os.getenv('LOG_LEVEL'))
+        except AttributeError as e:
+            logging.warning("Found 'LOG_LEVEL' env var, but was unable to parse: {}".format(e))
+        else:
+            logger.setLevel(numeric_level)
+            logger.debug('Set logging level to {!r} ({}) from env var'.format(log_level, numeric_level))
 
     URL = args.url
     FILE = getattr(args, 'ocaml-file')
@@ -224,7 +229,7 @@ def main():
     if not args.url:
         url_guess = infer_url(FILE)
         if not url_guess:  # break if filename can't be matched
-            logger.critical('Could not infer url from filename {!r}. Try passing a url manually with the `-u`/`--url` flag.'.format(FILE))
+            logger.critical('Could not infer url from filename {!r}. Try passing a url manually with the `--url` flag.'.format(FILE))
             sys.exit(1)
         else:
             URL = url_guess