1diff --git a/graphviz/backend.py b/graphviz/backend.py
2index 6f4cc0c..bc4781e 100644
3--- a/graphviz/backend.py
4+++ b/graphviz/backend.py
5@@ -122,7 +122,7 @@ def command(engine, format_, filepath=None, renderer=None, formatter=None):
6 raise ValueError('unknown formatter: %r' % formatter)
7
8 output_format = [f for f in (format_, renderer, formatter) if f is not None]
9- cmd = [engine, '-T%s' % ':'.join(output_format)]
10+ cmd = [os.path.join('@graphviz@/bin', engine), '-T%s' % ':'.join(output_format)]
11
12 if filepath is None:
13 rendered = None
14@@ -255,7 +255,7 @@ def version():
15 subprocess.CalledProcessError: If the exit status is non-zero.
16 RuntimmeError: If the output cannot be parsed into a version number.
17 """
18- cmd = ['dot', '-V']
19+ cmd = ['@graphviz@/bin/dot', '-V']
20 out, _ = run(cmd, check=True, encoding='ascii',
21 stdout=subprocess.PIPE,
22 stderr=subprocess.STDOUT)
23diff --git a/tests/test_backend.py b/tests/test_backend.py
24index 9f307f5..e43bf5b 100644
25--- a/tests/test_backend.py
26+++ b/tests/test_backend.py
27@@ -50,7 +50,7 @@ def test_run_encoding_mocked(mocker, Popen, input=u'sp\xe4m', encoding='utf-8'):
28 m.decode.assert_called_once_with(encoding)
29
30
31-@pytest.exe
32+@pytest.mark.skip(reason='empty $PATH has no effect')
33 @pytest.mark.usefixtures('empty_path')
34 @pytest.mark.parametrize('func, args', [
35 (render, ['dot', 'pdf', 'nonfilepath']),
36@@ -143,7 +143,7 @@ def test_render_mocked(capsys, mocker, Popen, quiet): # noqa: N803
37
38 assert render('dot', 'pdf', 'nonfilepath', quiet=quiet) == 'nonfilepath.pdf'
39
40- Popen.assert_called_once_with(['dot', '-Tpdf', '-O', 'nonfilepath'],
41+ Popen.assert_called_once_with(['@graphviz@/bin/dot', '-Tpdf', '-O', 'nonfilepath'],
42 stdout=subprocess.PIPE,
43 stderr=subprocess.PIPE,
44 cwd=None, startupinfo=mocker.ANY)
45@@ -201,7 +201,7 @@ def test_pipe_pipe_invalid_data_mocked(mocker, py2, Popen, quiet): # noqa: N803
46 assert e.value.stdout is mocker.sentinel.out
47 e.value.stdout = mocker.sentinel.new_stdout
48 assert e.value.stdout is mocker.sentinel.new_stdout
49- Popen.assert_called_once_with(['dot', '-Tpng'],
50+ Popen.assert_called_once_with(['@graphviz@/bin/dot', '-Tpng'],
51 stdin=subprocess.PIPE,
52 stdout=subprocess.PIPE,
53 stderr=subprocess.PIPE,
54@@ -224,7 +224,7 @@ def test_pipe_mocked(capsys, mocker, Popen, quiet): # noqa: N803
55
56 assert pipe('dot', 'png', b'nongraph', quiet=quiet) is mocker.sentinel.out
57
58- Popen.assert_called_once_with(['dot', '-Tpng'],
59+ Popen.assert_called_once_with(['@graphviz@/bin/dot', '-Tpng'],
60 stdin=subprocess.PIPE,
61 stdout=subprocess.PIPE,
62 stderr=subprocess.PIPE,
63@@ -250,7 +250,7 @@ def test_version_parsefail_mocked(mocker, Popen): # noqa: N803
64 with pytest.raises(RuntimeError, match=r'nonversioninfo'):
65 version()
66
67- Popen.assert_called_once_with(['dot', '-V'],
68+ Popen.assert_called_once_with(['@graphviz@/bin/dot', '-V'],
69 stdout=subprocess.PIPE,
70 stderr=subprocess.STDOUT,
71 startupinfo=mocker.ANY)
72@@ -269,7 +269,7 @@ def test_version_mocked(mocker, Popen, stdout, expected): # noqa: N803
73
74 assert version() == expected
75
76- Popen.assert_called_once_with(['dot', '-V'],
77+ Popen.assert_called_once_with(['@graphviz@/bin/dot', '-V'],
78 stdout=subprocess.PIPE,
79 stderr=subprocess.STDOUT,
80 startupinfo=mocker.ANY)