diff --git a/notmuch-git.py b/notmuch-git.py
index ce3c07bb..5475d0db 100644
--- a/notmuch-git.py
+++ b/notmuch-git.py
@@ -836,6 +836,10 @@ if __name__ == '__main__':
         level = getattr(_logging, args.log_level.upper())
         _LOG.setLevel(level)
 
+    # for test suite
+    for var in ['NMBGIT', 'NMBPREFIX', 'NOTMUCH_PROFILE', 'NOTMUCH_CONFIG' ]:
+        _LOG.debug('env {:s} = {:s}'.format(var, _os.getenv(var,'%None%')))
+
     if not getattr(args, 'func', None):
         parser.print_usage()
         _sys.exit(1)
diff --git a/test/T850-git.sh b/test/T850-git.sh
new file mode 100755
index 00000000..713b326f
--- /dev/null
+++ b/test/T850-git.sh
@@ -0,0 +1,93 @@
+#!/usr/bin/env bash
+test_description='"notmuch git" to save and restore tags'
+. $(dirname "$0")/test-lib.sh || exit 1
+
+add_email_corpus
+
+git config --global user.email notmuch@example.org
+git config --global user.name  "Notmuch Test Suite"
+
+test_begin_subtest "init"
+test_expect_success "notmuch git -p '' -C remote.git init"
+
+test_begin_subtest "clone"
+test_expect_success "notmuch git -p '' -C tags.git clone remote.git"
+
+test_begin_subtest "commit"
+notmuch git -C tags.git -p '' commit
+git -C tags.git ls-tree -r --name-only HEAD | xargs dirname | sort -u | sed s,tags/,id:, > OUTPUT
+notmuch search --output=messages '*' | sort > EXPECTED
+test_expect_equal_file_nonempty EXPECTED OUTPUT
+
+test_begin_subtest "checkout"
+notmuch dump > BEFORE
+notmuch tag -inbox '*'
+notmuch git -C tags.git -p '' checkout
+notmuch dump > AFTER
+test_expect_equal_file_nonempty BEFORE AFTER
+
+test_begin_subtest "archive"
+notmuch git -C tags.git -p '' archive | tar tf - | \
+    grep 20091117190054.GU3165@dottiness.seas.harvard.edu | sort > OUTPUT
+cat <<EOF > EXPECTED
+tags/20091117190054.GU3165@dottiness.seas.harvard.edu/
+tags/20091117190054.GU3165@dottiness.seas.harvard.edu/inbox
+tags/20091117190054.GU3165@dottiness.seas.harvard.edu/signed
+tags/20091117190054.GU3165@dottiness.seas.harvard.edu/unread
+EOF
+notmuch git -C tags.git -p '' checkout
+test_expect_equal_file EXPECTED OUTPUT
+
+test_begin_subtest "status"
+notmuch tag +test id:20091117190054.GU3165@dottiness.seas.harvard.edu
+notmuch git -C tags.git -p '' status > OUTPUT
+cat <<EOF > EXPECTED
+A	20091117190054.GU3165@dottiness.seas.harvard.edu	test
+EOF
+notmuch git -C tags.git -p '' checkout
+test_expect_equal_file EXPECTED OUTPUT
+
+test_begin_subtest "fetch"
+notmuch tag +test2 id:20091117190054.GU3165@dottiness.seas.harvard.edu
+notmuch git -C remote.git -p '' commit
+notmuch tag -test2 id:20091117190054.GU3165@dottiness.seas.harvard.edu
+notmuch git -C tags.git -p '' fetch
+notmuch git -C tags.git -p '' status > OUTPUT
+cat <<EOF > EXPECTED
+ a	20091117190054.GU3165@dottiness.seas.harvard.edu	test2
+EOF
+notmuch git -C tags.git -p '' checkout
+test_expect_equal_file EXPECTED OUTPUT
+
+test_begin_subtest "merge"
+notmuch git -C tags.git -p '' merge
+notmuch dump id:20091117190054.GU3165@dottiness.seas.harvard.edu | grep -v '^#' > OUTPUT
+cat <<EOF > EXPECTED
++inbox +signed +test2 +unread -- id:20091117190054.GU3165@dottiness.seas.harvard.edu
+EOF
+test_expect_equal_file EXPECTED OUTPUT
+
+test_begin_subtest "push"
+notmuch tag +test3 id:20091117190054.GU3165@dottiness.seas.harvard.edu
+notmuch git -C tags.git -p '' commit
+notmuch tag -test3 id:20091117190054.GU3165@dottiness.seas.harvard.edu
+notmuch git -C tags.git -p '' push
+notmuch git -C remote.git -p '' checkout
+notmuch dump id:20091117190054.GU3165@dottiness.seas.harvard.edu | grep -v '^#' > OUTPUT
+cat <<EOF > EXPECTED
++inbox +signed +test2 +test3 +unread -- id:20091117190054.GU3165@dottiness.seas.harvard.edu
+EOF
+test_expect_equal_file EXPECTED OUTPUT
+
+test_begin_subtest "environment passed through when run as 'notmuch git'"
+env NMBGIT=foo NMBPREFIX=bar NOTMUCH_PROFILE=default notmuch git -C tags.git -p '' -ldebug status |& \
+    grep '^env ' | notmuch_dir_sanitize > OUTPUT
+cat <<EOF > EXPECTED
+env NMBGIT = foo
+env NMBPREFIX = bar
+env NOTMUCH_PROFILE = default
+env NOTMUCH_CONFIG = CWD/notmuch-config
+EOF
+test_expect_equal_file EXPECTED OUTPUT
+
+test_done