diff --git a/README.md b/README.md
index d3a4a30..6a06173 100644
--- a/README.md
+++ b/README.md
@@ -79,7 +79,7 @@ after_success:
 
 
 ## CI Providers
-|                       Company                       |                                                                                     Supported                                                                                      |  Token Required  |
+|                       Company                         |                                                                                     Supported                                                                                      |  Token Required  |
 | ----------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------------- |
 | [AppVeyor](https://www.appveyor.com/)                 | Yes [![Build status](https://ci.appveyor.com/api/projects/status/sw18lsj7786bw806/branch/master?svg=true)](https://ci.appveyor.com/project/stevepeak/codecov-python/branch/master) | Private only     |
 | [Bamboo](https://www.atlassian.com/software/bamboo)   | `coming soon`                                                                                                                                                                      |                  |
@@ -96,6 +96,7 @@ after_success:
 | [Solano Labs](https://www.solanolabs.com/)            | `coming soon`                                                                                                                                                                      |                  |
 | [Travis CI](https://travis-ci.org/)                   | Yes [![Build Status](https://secure.travis-ci.org/codecov/codecov-python.svg?branch=master)](https://travis-ci.org/codecov/codecov-python)                                         | Private only     |
 | [Wercker](http://wercker.com/)                        | Yes                                                                                                                                                                                | Public & Private |
+| [Cirrus CI](https://cirrus-ci.org/)                   | Yes                                                                                                                                                                                | Private only     |
 | Git / Mercurial                                       | Yes (as a fallback)                                                                                                                                                                | Public & Private |
 
 
diff --git a/codecov/__init__.py b/codecov/__init__.py
index 9490dd4..99109ed 100644
--- a/codecov/__init__.py
+++ b/codecov/__init__.py
@@ -329,7 +329,7 @@ def main(*argv, **kwargs):
         "--token",
         "-t",
         default=os.getenv("CODECOV_TOKEN"),
-        help="Private repository token or @filename for file containing the token. Defaults to $CODECOV_TOKEN. Not required for public repositories on Travis CI, CircleCI and AppVeyor",
+        help="Private repository token or @filename for file containing the token. Defaults to $CODECOV_TOKEN. Not required for public repositories on Travis CI, CircleCI, AppVeyor and CirrusCI",
     )
     basics.add_argument(
         "--file",
@@ -845,6 +845,25 @@ def main(*argv, **kwargs):
 
             write("    GitHub Actions CI Detected")
 
+        # ---------
+        # Cirrus CI
+        # ---------
+        elif os.getenv("CIRRUS_CI"):
+            # https://cirrus-ci.org/guide/writing-tasks/#environment-variables
+            query.update(
+                dict(
+                    service="cirrus-ci",
+                    slug=os.getenv("CIRRUS_REPO_FULL_NAME"),
+                    branch=os.getenv("CIRRUS_BRANCH"),
+                    pr=os.getenv("CIRRUS_PR"),
+                    commit=os.getenv("CIRRUS_CHANGE_IN_REPO"),
+                    build=os.getenv("CIRRUS_BUILD_ID"),
+                    build_url="https://cirrus-ci.com/task/" + os.getenv("CIRRUS_TASK_ID"),
+                    job=os.getenv("CIRRUS_TASK_NAME"),
+                )
+            )
+            write("    Cirrus CI Detected")
+
         else:
             query.update(
                 dict(
diff --git a/tests/test.py b/tests/test.py
index d17a0f7..98a4412 100644
--- a/tests/test.py
+++ b/tests/test.py
@@ -879,6 +879,37 @@ def test_ci_github(self):
         self.assertEqual(res["codecov"].token, "token")
         self.assertEqual(res["codecov"].name, "name")
 
+    @unittest.skipUnless(
+        os.getenv("CI") == "true" and os.getenv("CIRRUS_CI") == "true",
+        "Skip Cirrus CI",
+    )
+    def test_ci_cirrus(self):
+        # The data used in this test follows the test case data in
+        # https://github.com/codecov/codecov-bash/pull/127
+        # Discussion about using codecov without token for Cirrus CI can be seen in:
+        # https://community.codecov.com/t/add-support-of-uploading-from-cirrus-ci-without-token/1028/36
+        self.set_env(
+            HOME="/",
+            CIRRUS_CI="true",
+            CIRRUS_REPO_FULL_NAME="codecov/ci-repo",
+            CIRRUS_BRANCH="master",
+            CIRRUS_PR="1",
+            CIRRUS_CHANGE_IN_REPO="180c0d097354fc1a451da8a3be5aba255f2ffd9f",
+            CIRRUS_BUILD_ID="777",
+            CIRRUS_TASK_ID="239",
+            CIRRUS_TASK_NAME="test"
+        )
+        self.fake_report()
+        res = self.run_cli()
+        self.assertEqual(res["query"]["service"], "cirrus-ci")
+        self.assertEqual(res["query"]["slug"], "codecov/ci-repo")
+        self.assertEqual(res["query"]["branch"], "master")
+        self.assertEqual(res["query"]["pr"], "1")
+        self.assertEqual(res["query"]["commit"], os.getenv("CIRRUS_CHANGE_IN_REPO"))
+        self.assertEqual(res["query"]["build"], "777")
+        self.assertEqual(res["query"]["build_url"], "https://cirrus-ci.com/task/239")
+        self.assertEqual(res["query"]["job"], "test")
+
     @unittest.skip("Skip CI None")
     def test_ci_none(self):
         self.set_env(CODECOV_TOKEN="token", CODECOV_NAME="name")