diff --git a/.travis.yml b/.travis.yml
index fe902344..d7d3d390 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,20 +2,16 @@ language: python
 matrix:
   include:
     - python: 3.5
-      env: TOX_ENV=py35
+      env: TOXENV=py35-coverage
     - python: 3.6
-      env: TOX_ENV=py36
+      env: TOXENV=py36-coverage
     - python: 3.7
-      env: TOX_ENV=py37
-      # TODO: the dist and sudo keys are currently needed to use Python 3.7.
-      # They should be removed once Travis-CI supports 3.7 on the default image.
-      dist: xenial
-      sudo: true
+      env: TOXENV=py37-coverage
 
-install: pip install tox-travis coveralls
+install: pip install tox
 
-script: tox -e $TOX_ENV
+script: tox
 
 after_success:
-  - tox -e coverage-report
-  - coveralls
+  - curl -S -L --connect-timeout 5 --retry 6 -s https://codecov.io/bash -o codecov-upload.sh
+  - bash codecov-upload.sh -Z -X fix -f coverage.xml
diff --git a/README.rst b/README.rst
index 9695de4d..24c5c378 100644
--- a/README.rst
+++ b/README.rst
@@ -5,8 +5,9 @@ pytest-asyncio: pytest support for asyncio
     :target: https://pypi.python.org/pypi/pytest-asyncio
 .. image:: https://travis-ci.org/pytest-dev/pytest-asyncio.svg?branch=master
     :target: https://travis-ci.org/pytest-dev/pytest-asyncio
-.. image:: https://coveralls.io/repos/pytest-dev/pytest-asyncio/badge.svg
-    :target: https://coveralls.io/r/pytest-dev/pytest-asyncio
+.. image:: https://codecov.io/gh/pytest-dev/pytest-asyncio/branch/master/graph/badge.svg
+    :target: https://codecov.io/gh/pytest-dev/pytest-asyncio
+    :alt: Code coverage Status
 .. image:: https://img.shields.io/pypi/pyversions/pytest-asyncio.svg
     :target: https://github.com/pytest-dev/pytest-asyncio
     :alt: Supported Python versions
diff --git a/codecov.yml b/codecov.yml
new file mode 100644
index 00000000..a0a30858
--- /dev/null
+++ b/codecov.yml
@@ -0,0 +1,7 @@
+coverage:
+  status:
+    project: true
+    patch: true
+    changes: true
+
+comment: off
diff --git a/setup.cfg b/setup.cfg
index 4a0e3005..dd344b18 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,8 +1,14 @@
 [coverage:run]
-source = pytest_asyncio
+source = pytest_asyncio,tests
+branch = 1
 
 [coverage:report]
-show_missing = true
+show_missing = 1
+skip_covered = 1
+exclude_lines =
+    \#\s*pragma: no cover
+    ^\s*raise NotImplementedError\b
+    ^\s*return NotImplemented\b
 
 [tool:pytest]
 addopts = -rsx --tb=short
diff --git a/setup.py b/setup.py
index 8c074a24..4605fec5 100644
--- a/setup.py
+++ b/setup.py
@@ -44,7 +44,6 @@ def find_version():
     extras_require={
         ':python_version == "3.5"': "async_generator >= 1.3",
         "testing": [
-            "coverage",
             "async_generator >= 1.3",
             "hypothesis >= 3.64",
         ],
diff --git a/tests/test_simple.py b/tests/test_simple.py
index 1627139d..b79daf33 100644
--- a/tests/test_simple.py
+++ b/tests/test_simple.py
@@ -42,7 +42,7 @@ async def test_unused_port_fixture(unused_tcp_port, event_loop):
     """Test the unused TCP port fixture."""
 
     async def closer(_, writer):
-        writer.close()
+        raise NotImplementedError()
 
     server1 = await asyncio.start_server(closer, host='localhost',
                                          port=unused_tcp_port,
@@ -62,7 +62,7 @@ async def test_unused_port_factory_fixture(unused_tcp_port_factory, event_loop):
     """Test the unused TCP port factory fixture."""
 
     async def closer(_, writer):
-        writer.close()
+        raise NotImplementedError()
 
     port1, port2, port3 = (unused_tcp_port_factory(), unused_tcp_port_factory(),
                            unused_tcp_port_factory())
diff --git a/tests/test_simple_35.py b/tests/test_simple_35.py
index 1e4d697c..a545444d 100644
--- a/tests/test_simple_35.py
+++ b/tests/test_simple_35.py
@@ -24,7 +24,7 @@ async def test_asyncio_marker_with_default_param(a_param=None):
 async def test_unused_port_fixture(unused_tcp_port, event_loop):
     """Test the unused TCP port fixture."""
     async def closer(_, writer):
-        writer.close()
+        raise NotImplementedError()
 
     server1 = await asyncio.start_server(closer, host='localhost',
                                          port=unused_tcp_port,
@@ -38,7 +38,7 @@ def test_unused_port_factory_fixture(unused_tcp_port_factory, event_loop):
     """Test the unused TCP port factory fixture."""
 
     async def closer(_, writer):
-        writer.close()
+        raise NotImplementedError()
 
     port1, port2, port3 = (unused_tcp_port_factory(), unused_tcp_port_factory(),
                            unused_tcp_port_factory())
diff --git a/tox.ini b/tox.ini
index 13d5155a..5c83f6de 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,11 +4,10 @@ minversion = 2.5.0
 
 [testenv]
 extras = testing
-commands = coverage run -m pytest {posargs}
-
-[testenv:coverage-report]
-deps = coverage
-skip_install = true
-commands =
-    coverage combine
-    coverage report
+deps =
+  coverage: coverage
+commands = {env:COVERAGE_RUN:pytest} {posargs}
+  coverage: coverage report -m
+  coverage: coverage xml
+setenv =
+  coverage: COVERAGE_RUN=coverage run -m pytest