diff --git a/.travis.yml b/.travis.yml
index 38543845a..16cb6f23f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -63,6 +63,10 @@ matrix:
       env: TOXENV=nginxroundtrip
 
     # These environments are executed on cron events only
+    - python: "3.7"
+      dist: xenial
+      env: TOXENV=py37 CERTBOT_NO_PIN=1
+      if: type = cron
     - python: "2.7"
       env: BOULDER_INTEGRATION=v1 INTEGRATION_TEST=certbot TOXENV=py27-certbot-oldest
       sudo: required
diff --git a/acme/acme/messages.py b/acme/acme/messages.py
index 4400a6c31..7c82c8507 100644
--- a/acme/acme/messages.py
+++ b/acme/acme/messages.py
@@ -1,7 +1,10 @@
 """ACME protocol messages."""
-import collections
 import six
 import json
+try:
+    from collections.abc import Hashable  # pylint: disable=no-name-in-module
+except ImportError:
+    from collections import Hashable
 
 import josepy as jose
 
@@ -107,7 +110,7 @@ class Error(jose.JSONObjectWithFields, errors.Error):
             if part is not None).decode()
 
 
-class _Constant(jose.JSONDeSerializable, collections.Hashable):  # type: ignore
+class _Constant(jose.JSONDeSerializable, Hashable):  # type: ignore
     """ACME constant."""
     __slots__ = ('name',)
     POSSIBLE_NAMES = NotImplemented
diff --git a/pytest.ini b/pytest.ini
index 9a5807f34..8f009045c 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -3,10 +3,14 @@
 # directly.
 [pytest]
 addopts = --numprocesses auto --pyargs
-# ResourceWarnings are ignored as errors, since they're raised at close
-# decodestring: https://github.com/rthalley/dnspython/issues/338
-# ignore our own TLS-SNI-01 warning
+# In general, all warnings are treated as errors. Here are the exceptions:
+#   1- decodestring: https://github.com/rthalley/dnspython/issues/338
+#   2- ignore our own TLS-SNI-01 warning
+#   3- ignore warn for importing abstract classes from collections instead of collections.abc,
+#      too much third party dependencies are still relying on this behavior,
+#      but it should be corrected to allow Certbot compatiblity with Python >= 3.8
 filterwarnings =
     error
     ignore:decodestring:DeprecationWarning
     ignore:TLS-SNI-01:DeprecationWarning
+    ignore:.*collections\.abc:DeprecationWarning
diff --git a/tools/install_and_test.py b/tools/install_and_test.py
index 79a7c2264..0142eeea4 100755
--- a/tools/install_and_test.py
+++ b/tools/install_and_test.py
@@ -17,16 +17,15 @@ import re
 SKIP_PROJECTS_ON_WINDOWS = [
     'certbot-apache', 'certbot-nginx', 'certbot-postfix', 'letshelp-certbot']
 
+
 def call_with_print(command, cwd=None):
     print(command)
     subprocess.check_call(command, shell=True, cwd=cwd or os.getcwd())
 
+
 def main(args):
-    if os.environ.get('CERTBOT_NO_PIN') == '1':
-        command = [sys.executable, '-m', 'pip', '-e']
-    else:
-        script_dir = os.path.dirname(os.path.abspath(__file__))
-        command = [sys.executable, os.path.join(script_dir, 'pip_install_editable.py')]
+    script_dir = os.path.dirname(os.path.abspath(__file__))
+    command = [sys.executable, os.path.join(script_dir, 'pip_install_editable.py')]
 
     new_args = []
     for arg in args:
diff --git a/tools/pip_install.py b/tools/pip_install.py
index 4466729e0..332422019 100755
--- a/tools/pip_install.py
+++ b/tools/pip_install.py
@@ -80,19 +80,26 @@ def main(args):
         test_constraints = os.path.join(working_dir, 'test_constraints.txt')
         all_constraints = os.path.join(working_dir, 'all_constraints.txt')
 
-        requirements = None
-        if os.environ.get('CERTBOT_OLDEST') == '1':
-            requirements = certbot_oldest_processing(tools_path, args, test_constraints)
+        if os.environ.get('CERTBOT_NO_PIN') == '1':
+            # With unpinned dependencies, there is no constraint
+            call_with_print('"{0}" -m pip install --ignore-installed {1}'
+                            .format(sys.executable, ' '.join(args)))
         else:
-            certbot_normal_processing(tools_path, test_constraints)
+            # Otherwise, we merge requirements to build the constraints and pin dependencies
+            requirements = None
+            if os.environ.get('CERTBOT_OLDEST') == '1':
+                requirements = certbot_oldest_processing(tools_path, args, test_constraints)
+            else:
+                certbot_normal_processing(tools_path, test_constraints)
 
-        merge_requirements(tools_path, test_constraints, all_constraints)
-        if requirements:
-            call_with_print('"{0}" -m pip install --constraint "{1}" --requirement "{2}"'
-                            .format(sys.executable, all_constraints, requirements))
+            merge_requirements(tools_path, test_constraints, all_constraints)
 
-        call_with_print('"{0}" -m pip install --constraint "{1}" {2}'
-                        .format(sys.executable, all_constraints, ' '.join(args)))
+            if requirements:
+                call_with_print('"{0}" -m pip install --constraint "{1}" --requirement "{2}"'
+                                .format(sys.executable, all_constraints, requirements))
+
+            call_with_print('"{0}" -m pip install --constraint "{1}" {2}'
+                            .format(sys.executable, all_constraints, ' '.join(args)))
     finally:
         if os.environ.get('TRAVIS'):
             print('travis_fold:end:install_certbot_deps')
diff --git a/tox.ini b/tox.ini
index 36057b5df..363f06bf2 100644
--- a/tox.ini
+++ b/tox.ini
@@ -64,6 +64,8 @@ source_paths =
     tests/lock_test.py
 
 [testenv]
+passenv =
+    CERTBOT_NO_PIN
 commands =
     {[base]install_and_test} {[base]all_packages}
     python tests/lock_test.py