diff --git a/dev.in b/dev.in
index db4b64e..931fd5d 100644
--- a/dev.in
+++ b/dev.in
@@ -1,7 +1,7 @@
 bumpversion==0.5.3
 check-manifest==0.41
 coverage==5.0.3
-pip-tools==4.5.1
+pip-tools==6.9.0
 pytest-runner==5.2
 pytest-watch==4.2.0
 pytest==5.3.5
diff --git a/dev.txt b/dev.txt
index 420468b..5c4db87 100644
--- a/dev.txt
+++ b/dev.txt
@@ -12,6 +12,8 @@ babel==2.8.0
     # via sphinx
 bleach==3.1.4
     # via readme-renderer
+build==0.8.0
+    # via pip-tools
 bumpversion==0.5.3
     # via -r dev.in
 certifi==2019.11.28
@@ -56,14 +58,17 @@ more-itertools==8.2.0
     # via pytest
 packaging==20.1
     # via
+    #   build
     #   pytest
     #   sphinx
     #   tox
 pathtools==0.1.2
     # via watchdog
-pep517==0.8.1
-    # via check-manifest
-pip-tools==4.5.1
+pep517==0.13.0
+    # via
+    #   build
+    #   check-manifest
+pip-tools==6.9.0
     # via -r dev.in
 pkginfo==1.5.0.1
     # via twine
@@ -83,25 +88,25 @@ pygments==2.5.2
     #   sphinx
 pyparsing==2.4.6
     # via packaging
-pytest-runner==5.2
-    # via -r dev.in
-pytest-watch==4.2.0
-    # via -r dev.in
 pytest==5.3.5
     # via
     #   -r dev.in
     #   pytest-watch
+pytest-runner==5.2
+    # via -r dev.in
+pytest-watch==4.2.0
+    # via -r dev.in
 pytz==2019.3
     # via babel
 readme-renderer==24.0
     # via twine
-requests-toolbelt==0.9.1
-    # via twine
 requests==2.22.0
     # via
     #   requests-toolbelt
     #   sphinx
     #   twine
+requests-toolbelt==0.9.1
+    # via twine
 secretstorage==3.1.2
     # via keyring
 six==1.14.0
@@ -109,7 +114,6 @@ six==1.14.0
     #   bleach
     #   cryptography
     #   packaging
-    #   pip-tools
     #   readme-renderer
     #   tox
 snowballstemmer==2.0.0
@@ -131,8 +135,11 @@ sphinxcontrib-serializinghtml==1.1.3
 toml==0.10.0
     # via
     #   check-manifest
-    #   pep517
     #   tox
+tomli==2.0.1
+    # via
+    #   build
+    #   pep517
 tox==3.14.5
     # via -r dev.in
 tqdm==4.42.0
@@ -152,7 +159,10 @@ wcwidth==0.1.8
 webencodings==0.5.1
     # via bleach
 wheel==0.34.2
-    # via -r dev.in
+    # via
+    #   -r dev.in
+    #   pip-tools
 
 # The following packages are considered to be unsafe in a requirements file:
+# pip
 # setuptools