diff --git a/.github/.OwlBot.lock.yaml b/.github/.OwlBot.lock.yaml
index efbc4b3..e2b39f9 100644
--- a/.github/.OwlBot.lock.yaml
+++ b/.github/.OwlBot.lock.yaml
@@ -1,3 +1,3 @@
 docker:
   image: gcr.io/repo-automation-bots/owlbot-python:latest
-  digest: sha256:df50e8d462f86d6bcb42f27ecad55bb12c404f1c65de9c6fe4c4d25120080bd6
\ No newline at end of file
+  digest: sha256:99d90d097e4a4710cc8658ee0b5b963f4426d0e424819787c3ac1405c9a26719
diff --git a/CHANGELOG.md b/CHANGELOG.md
index cc9fae5..d99f8ea 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+### [0.1.5](https://www.github.com/googleapis/python-access-context-manager/compare/v0.1.4...v0.1.5) (2021-07-07)
+
+
+### Bug Fixes
+
+* require google-api-core >= 1.26.0 ([#57](https://www.github.com/googleapis/python-access-context-manager/issues/57)) ([12ddfa5](https://www.github.com/googleapis/python-access-context-manager/commit/12ddfa58a5c4951da5753858701a83b297d38be2))
+
 ### [0.1.4](https://www.github.com/googleapis/python-access-context-manager/compare/v0.1.3...v0.1.4) (2021-06-22)
 
 
diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
index 3fb9f8e..6bf91c5 100644
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -68,14 +68,12 @@ Using ``nox``
 We use `nox <https://nox.readthedocs.io/en/latest/>`__ to instrument our tests.
 
 - To test your changes, run unit tests with ``nox``::
+    $ nox -s unit
 
-    $ nox -s unit-3.8
-    $ ...
+- To run a single unit test::
 
-- Args to pytest can be passed through the nox command separated by a `--`. For
-  example, to run a single test::
+    $ nox -s unit-3.9 -- -k <name of test>
 
-    $ nox -s unit-3.8 -- -k <name of test>
 
   .. note::
 
@@ -142,7 +140,7 @@ Running System Tests
 - To run system tests, you can execute::
 
    # Run all system tests
-   $ nox -s system-3.8
+   $ nox -s system
 
    # Run a single system test
    $ nox -s system-3.8 -- -k <name of test>
@@ -215,8 +213,8 @@ Supported versions can be found in our ``noxfile.py`` `config`_.
 .. _config: https://github.com/googleapis/python-access-context-manager/blob/master/noxfile.py
 
 
-We also explicitly decided to support Python 3 beginning with version
-3.6. Reasons for this include:
+We also explicitly decided to support Python 3 beginning with version 3.6.
+Reasons for this include:
 
 -  Encouraging use of newest versions of Python 3
 -  Taking the lead of `prominent`_ open-source `projects`_
diff --git a/noxfile.py b/noxfile.py
index 3409852..500eca3 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -28,8 +28,8 @@
 BLACK_PATHS = ["docs", "google", "tests", "noxfile.py", "setup.py"]
 
 DEFAULT_PYTHON_VERSION = "3.8"
-SYSTEM_TEST_PYTHON_VERSIONS = ["2.7", "3.8"]
-UNIT_TEST_PYTHON_VERSIONS = ["2.7", "3.6", "3.7", "3.8", "3.9"]
+SYSTEM_TEST_PYTHON_VERSIONS = ["3.8"]
+UNIT_TEST_PYTHON_VERSIONS = ["3.6", "3.7", "3.8", "3.9"]
 
 CURRENT_DIRECTORY = pathlib.Path(__file__).parent.absolute()
 
@@ -84,6 +84,8 @@ def default(session):
     constraints_path = str(
         CURRENT_DIRECTORY / "testing" / f"constraints-{session.python}.txt"
     )
+    session.install("asyncmock", "pytest-asyncio", "-c", constraints_path)
+
     session.install("mock", "pytest", "pytest-cov", "-c", constraints_path)
 
     session.install("-e", ".", "-c", constraints_path)
diff --git a/owlbot.py b/owlbot.py
index c94f6f6..86734c5 100644
--- a/owlbot.py
+++ b/owlbot.py
@@ -24,7 +24,7 @@
 #  Add templated files
 # ----------------------------------------------------------------------------
 common = gcp.CommonTemplates()
-templated_files = common.py_library()
+templated_files = common.py_library(microgenerator=True)
 s.move(
     templated_files, excludes=[".coveragerc", ".gitignore",],
 )
diff --git a/setup.py b/setup.py
index 2e0ea9c..fd2acf9 100644
--- a/setup.py
+++ b/setup.py
@@ -21,13 +21,13 @@
 
 name = "google-cloud-access-context-manager"
 description = "Google Cloud Access Context Manager Protobufs"
-version = "0.1.4"
+version = "0.1.5"
 # Should be one of:
 # 'Development Status :: 3 - Alpha'
 # 'Development Status :: 4 - Beta'
 # 'Development Status :: 5 - Production/Stable'
 release_status = "Development Status :: 4 - Beta"
-dependencies = ["google-api-core[grpc] >= 1.22.2, < 2.0.0dev", "protobuf >= 3.12.0"]
+dependencies = ["google-api-core[grpc] >= 1.26.0, < 2.0.0dev", "protobuf >= 3.12.0"]
 
 # Setup boilerplate below this line.
 
diff --git a/testing/constraints-3.6.txt b/testing/constraints-3.6.txt
index 352cc81..37118f4 100644
--- a/testing/constraints-3.6.txt
+++ b/testing/constraints-3.6.txt
@@ -6,4 +6,4 @@
 # e.g., if setup.py has "foo >= 1.14.0, < 2.0.0dev",
 # Then this file should have foo==1.14.0
 protobuf==3.12.0
-google-api-core==1.22.2
+google-api-core==1.26.0